Jin @ .NET: TIPS and TRICKS

ASP.NET Session State

2012-01-26T03:05:00.001+08:00

What is session state?

· The heavy weight of state management, it allows information to store in one page to another.

· It supports any type of object, which includes custom data types.

· It also uses the same collection syntax as view state.

· It is also considered similar to application state. However, session stated scopes only current browser(user session) and only available to that session unlike application state which scopes the entire application.

ASP.NET provides the following session storage options:

· InProc

o actually this is the default condition, and it makes sense for most small websites. Moreover, it stores session state in memory on the web server.

o It is also a good choice for small applications. However, in a web farm scenario, though, it won't work at all to allow Session State to be shared between servers, you may use the StateServer or SQLServer.

· StateServer

o it actually stores session state in a service called the ASP.NET State Service.

o Session state is preserved even if the web application is restarted and makes available to multiple-web servers in a web farm.

· SQLServer

o Actually stores the session state in a SQL Server database(of course you need a server with SQL Server installed :->). However, it is quite slow compare to StateServer.

o Also offers more robust data integrity and reporting capabilities.

Steps to use the SQLServer mode

1. Using aspnet_regsql for session state

aspnet_regsql -S -U -P -d -sstype t|p|c -ssadd

2. configure web.config

3. Let's try to play around using Session

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace SQlServerMode
{
    public partial class Default : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!this.IsPostBack)
                Session["MySampleSession"] = DateTime.Now;
            else
                this.lblSessionValue.Text = string.Format ("You entered this page around: {0}",
                        Session["MySampleSession"]);
        }

        protected void btnClickMe_Click(object sender, EventArgs e)
        {
            this.lblButtonTimeAfterClick.Text = string.Format("You clicked the button around: {0}", DateTime.Now);

        }
    }
}

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="SQlServerMode.Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
<asp:Label ID="lblSessionValue" runat="server" Text=""></asp:Label>
<br />
<asp:Label ID="lblButtonTimeAfterClick" runat="server" Text=""></asp:Label>
<br />
<asp:Button ID="btnClickMe" runat="server" onclick="btnClickMe_Click" Text="Just Click Me to show session value" />
</div>
</form>
</body>
</html>

Result

The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).

2011-08-16T00:44:00.002+08:00

Here's what I did, I change <%= %> to <%# %>
As you can see im using the <%= %>


using <%= %>

Solution: so I replaced it with <%# %>

Work's great!

Also put this on the page load event of your masterpage!
this.Page.Header.DataBind();

Using IEnumerator and IEnumerable in the .NET Framework

2011-04-16T16:50:00.001+08:00

In this post I actually created a simple program using C# that implements IEnumerator and IEnumerable.
So if you are interested let's get started....

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;
namespace IEnumSamp
{
    class Program
    {
        static void Main(string[] args)
        {

            clsEmployee[] emp = new clsEmployee[]
            {   new clsEmployee("rhian", "calzado", 30),
                new clsEmployee("jin", "necesario", 29),
                new clsEmployee("rouie", "andes", 30)
            };

            EmployeeCollection myEmployees = 
                        new EmployeeCollection(emp);

            IEnumerator EmpEnum = myEmployees.GetEnumerator();

            while (EmpEnum.MoveNext())
            {
                Console.WriteLine(((clsEmployee)(EmpEnum.Current)).FirstName);
            }

            foreach (clsEmployee emp_ in myEmployees)
            {
                Console.WriteLine(emp_.ToString());
            }
        }
    }
}

using System;
using System.Collections.Generic;
using System.Collections;
using System.Linq;
using System.Text;

namespace IEnumSamp
{
    public class clsEmployee
    {
        private string strFirstName;
        private string strLastName;
        private int intAge;

        public clsEmployee(string fname, string lname, int age)
        {
            this.strFirstName = fname;
            this.strLastName = lname;
            this.intAge = age;
        }

        public string FirstName
        {
            get
            {
                return this.strFirstName;
            }
        }

        public string LastName
        {
            get
            {
                return this.strLastName; 
            }
        }

        public int Age
        {
            get
            {
                return this.intAge;
            }
        }

        public override string ToString()
        {
            return "Fullname: " + this.strLastName + ", " + this.strFirstName + " Age: " +this.intAge.ToString ();

        }
    }

    public class EmployeeCollection : IEnumerable
    {
        private clsEmployee[] emp_;

        public EmployeeCollection(clsEmployee[] emp)
        {
            if (emp.GetType() == typeof(clsEmployee[]))
            {
                emp_ = emp;
            }
            else
                throw new ArgumentException("invalid type");
        }

        #region IEnumerable Members

        public IEnumerator GetEnumerator()
        {
            return (IEnumerator)new EmployeeEnum(emp_);
        }

        #endregion
    }

    public class EmployeeEnum : IEnumerator
    {
       private clsEmployee[] empList = null;

       public EmployeeEnum(clsEmployee[] emp)
       {
           if (emp.GetType() == typeof(clsEmployee[]))
           {
               empList = emp;
           }
           else
               throw new ArgumentException("invalid type");
       }

       private int intPosition=-1;

        #region IEnumerator Members

        public object Current
        {
            get 
            {
                if (intPosition < 0)
                    throw new InvalidOperationException();
                if (intPosition > empList.Length)
                    throw new InvalidOperationException();

                    return empList[intPosition];
            }
        }

        public bool MoveNext()
        {
            this.intPosition++;

            if (this.intPosition >= empList.Length)
                return false;
            else
                return true;
        }

        public void Reset()
        {
            this.intPosition = -1;
        }

        #endregion
    }

}

ICloneable

2011-03-30T21:34:00.001+08:00

Are you interested on how to use IClonable Interface? I hope this will give you an idea!

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace SampleIClonable
{
    public class clsPerson : ICloneable 
    {

        private string strFirstName;
        private string strLastName;
        private clsPerson Father;

        public clsPerson(string FName, string LName)
        {
            this.strFirstName = FName;
            this.strLastName = LName;
        }

        public clsPerson father
        {
            get 
            {
                if (this.Father != null)
                    return this.Father;
                else
                    throw new ArgumentException("object null");
            }

            set 
            {
                if (value.GetType() == typeof(clsPerson))
                    this.Father = value;
                else
                    throw new ArgumentException("Invalid type");    
            }
        
        }

        public string FName
        {
            get { return this.strFirstName; }
        }

        public string LName
        {
            get { return this.strLastName; }
        }

        #region ICloneable Members

        public object Clone()
        {
            return this.MemberwiseClone();
        }

        #endregion
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace SampleIClonable
{
    class Program
    {
        static void Main(string[] args)
        {
            //let's define clsPerson and his father

            clsPerson FirstPerson = new clsPerson("Jin Vincent", "Necesario");

            clsPerson SecondPerson = new clsPerson("Jess", "Necesario");

            FirstPerson.father = SecondPerson;

            //let's clone it
            clsPerson FirstPerson2 = (clsPerson)FirstPerson.Clone();

            Console.WriteLine("First Name: {0} Last Name: {1} \r\nFather: {2} {3}", 
                FirstPerson2.FName ,FirstPerson2.LName  , 
                FirstPerson2.father.FName, FirstPerson2.father.LName);  


        }
    }
}

Difference between IComparable and IComparer

2011-03-20T23:08:00.002+08:00

Do you wan to know the difference between IComparable and IComparer! just check my sample below! thanks.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace IComparableSamples
{
    /*
     * I hope gives you an idea 
     * what's the difference between the
     * icomparer and icomparable 
     * ----------------------------------------------------------------------
     * IComparable - provides a method of comparing 
     * two objects of a particular type. (in only one way)
     * IComparer - allows you to sort object on different fields combinations
     * so let's start to explore! 
     * sorry for my poor english! :->
     * Mr. Jin Vincent N. Necesario
     * if you think my code needs some improvement please email me at 
     * jin29_neci@hotmail.com, jin29neci@gmail.com thank you!
     */

    class Program
    {
        static void Main(string[] args)
        {
            //let's create some employee's 

            Employee_[] arrOfEmployee = new Employee_[] { 
                new Employee_ ("Michael", "Enriquez", "Calzado",1980),
                new Employee_ ("John", "Chua", "Cruz",1978),
                new Employee_ ("Chris", "Brown","Gold", 2007),
                new Employee_("Cony","JeSan", "Nequez", 2010),
                new Employee_("Johnny","Aban", "Uno", 2006),
            };

            Console.WriteLine("------Unsorted------\n\r");
            
            //let's display the unsorted employee's
            
            foreach (Employee_ emp in arrOfEmployee)
            {
                Console.WriteLine(emp.ReturnFullName);

            }

            Console.WriteLine("\n\r");

            //after creating some employee's let's try to sort the Employe_ class

            Array.Sort(arrOfEmployee);

            Console.WriteLine("------Sorted------\n\r");

            foreach (Employee_ emp in arrOfEmployee)
            {
               Console.WriteLine (emp.ReturnFullName);

            }
            
            Console.WriteLine("\n\r");

            //let's try to reverse the order

            Array.Reverse(arrOfEmployee);

            Console.WriteLine("----Sorted Reverse Order----\n\r");

            foreach (Employee_ emp in arrOfEmployee)
            {
                Console.WriteLine(emp.ReturnFullName);

            }
            Console.WriteLine("\n\r");

            //let's try to sort using the IComparer

            Array.Sort(arrOfEmployee, new ComparerByFullNameWithMiddleName());

            //let's display the unsorted employee's

            Console.WriteLine("----Icomparer Sort Full name with middle name----\n\r");

            foreach (Employee_ emp in arrOfEmployee)
            {
                Console.WriteLine(emp.ReturnFullNameWithMiddleName);

            }
            
            Console.WriteLine("\n\r");
            
            //let's try to sort using the IComparer

            Array.Sort(arrOfEmployee, new ComparerByYearEntry());
            
            Console.WriteLine("----Icomparer Sort Year Entry----\n\r");
            
            foreach (Employee_ emp in arrOfEmployee)
            {
                Console.WriteLine(emp.ReturnFullNameWithMiddleName +" " + emp.ReturnYearEntry );
            }


            Console.ReadKey();
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace IComparableSamples
{
    class Employee_:IComparable 
    {
        private string strEmployeeFirstName;
        private string strEmployeeLastName;
        private string strEmployeeMiddleName;
        private int intYearEntry;

        public Employee_():this("","","")
        {

        }

        public Employee_(string fName)
        {
            this.strEmployeeFirstName = fName;
        }

        public Employee_(string fName, string lName)
        {
            this.strEmployeeFirstName = fName;
            this.strEmployeeLastName = lName;
        }


        public Employee_(string fName, string lName, string lMName)
        {
            this.strEmployeeFirstName = fName;
            this.strEmployeeLastName = lName;
            this.strEmployeeMiddleName = lMName;
        }


        public Employee_(string fName, string lName, string lMName, int year)
        {
            this.strEmployeeFirstName = fName;
            this.strEmployeeLastName = lName;
            this.strEmployeeMiddleName = lMName;
            this.intYearEntry = year;
        }

        #region Properties

        //returns the employee's fullname
        public string ReturnFullName
        {
            get {
                return string.Concat(this.strEmployeeLastName, ", ", this.strEmployeeFirstName); 
            }
        }

        //returns the employee's fullname with middlename
        public string ReturnFullNameWithMiddleName
        {
            get
            {
                return string.Concat(this.strEmployeeLastName, ", ", this.strEmployeeFirstName, this.strEmployeeMiddleName);
            }
        }

        //returns the employee's fullname with middlinitial
        
        public string ReturnFullNameWithMiddleInitialOnly
        {
            get
            {
                return string.Concat(this.strEmployeeLastName, ", ", this.strEmployeeFirstName, " ", this.strEmployeeMiddleName[0].ToString().ToUpper(), ".");
            }
        }

        public int ReturnYearEntry
        {
            get {
                return this.intYearEntry;
            }
        }

        #endregion 


        #region IComparable Members

        //adds sorting capability to this class

        public int CompareTo(object obj)
        {
            int intRet=0;

            if (obj == null)
                intRet = 1;
            else
            {
                //let's try to cast the object to Employee_; error if the argument is a different type
                Employee_ anotherEmployee = (Employee_)obj;

                //ignore case just compare
                intRet = string.Compare(this.ReturnFullName , anotherEmployee.ReturnFullName, true);
            }

            return intRet;
        }

        #endregion
    }
public class ComparerByFullNameWithMiddleName : IComparer<Employee_>
{
    #region IComparer<Employee_> Members

    int IComparer<Employee_>.Compare(Employee_ emp1, Employee_ emp2)
    {
        return string.Compare(emp1.ReturnFullNameWithMiddleName, emp2.ReturnFullNameWithMiddleName); 
    }

    #endregion
}
public class ComparerByYearEntry : IComparer<Employee_>
{

    #region IComparer<Employee_> Members

    int IComparer<Employee_>.Compare(Employee_ emp1, Employee_ emp2)
    {
        if (emp1.ReturnYearEntry > emp2.ReturnYearEntry)
            return 1;
        if (emp1.ReturnYearEntry < emp2.ReturnYearEntry)
            return -1;
        else
            return 0;
    }

    #endregion
}
}

The Microsoft.ACE.OLEDB.12.0 provider is not registered on the local machine.

2011-02-24T01:14:00.000+08:00

just download 2007 Office System Driver: Data Connectivity Components

this can be downloaded at:microsoft download center

HTTP Error 500.21 - Internal Server Error

2011-02-16T00:09:00.003+08:00

have you ever experienced this kind of error!

here' s what I did!

and ta-da! back to normal.

Encrypt connectionstrings section in Appconfig file C#

2010-11-06T15:31:00.005+08:00

As we all know there are a lot of reasons why we should encrypt/protect our configuration file or the app.config file for windows(winforms). So if you are interested on how to do it.
Read on.....

Here is my configuration file
App.config

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Configuration;
using System.Data.OleDb;

namespace EncryptAppConfigFile
{
    public partial class frmConenctionString : Form
    {
        public frmConenctionString()
        {
            InitializeComponent();
        }

       
       /// 
       /// if the user clicks this button(protect button) let's try to encrypt our configuration file(app.config)
       /// 
        private void btnProctect_Click(object sender, EventArgs e)
        {
           
            //open the configuration file, 

            Configuration myConfig = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);

            //after opening lets get the connection string section
            
            ConnectionStringsSection mySection = myConfig.ConnectionStrings;


            if (mySection != null)
            {
                // if the connectionstring is not protected we have to protect the section
                if (!mySection.SectionInformation.IsProtected)
                {
                   
                    mySection.SectionInformation.ProtectSection("RsaProtectedConfigurationProvider");
                    mySection.SectionInformation.ForceSave = true;
                }
            }

            myConfig.Save(ConfigurationSaveMode.Full);
        }

        private void btnGetSomething_Click(object sender, EventArgs e)
        {
            
            // someone ask me!
            // question: if the <connectionstring> section is encrypted can it still be used to open a database
            // ans: yes

            using (OleDbConnection con = new OleDbConnection(ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString))
            { 
                using(OleDbCommand cmd = new OleDbCommand ("SELECT TOP 1 Company FROM Customers",con))
                {
                    con.Open();

                    using (OleDbDataReader rdr = cmd.ExecuteReader())
                    {
                        if (rdr.HasRows)
                        {
                            rdr.Read();

                            MessageBox.Show(rdr[0].ToString());
                        }
                    }
                }
            }
        }
    }
}

Protected/Encrypted Appconfig.file

If someone wishes to click the button(Protect Connection String) -> see results below


 
  
   
   
    
     
     
      Rsa Key
     
     
      j7AJRpyn3yF2XwTwWkm7BAKvMBxPaLphuIYgrBKN0Cvct6gaU0/56btcWx9bpXMpJ8LteANXmetIUtPJ44zIQV/X2VY2vEbJPUZg8C+qhGYblOrPz05FO89W7onAeb5ZNjI0QpKtovG3jmVmf2kZvEW4RFxo5s2Vep1N1ykIXoU=
     
    
   
   
    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

sample output(connecting and fectching a record while app.config file/connectionstring is protected)!

Retrieving network computer names c#

2010-10-22T19:52:00.003+08:00

Recently someone told me, he couldn't get the name of the computers on the network! so I tried to create and used some .net libraries but i couldn't get the name of the computer either.

I'm only getting the I.P. address of computers on the certain network, so I look for some articles that could help me out! and found this micorosft's documentation click here

As you can see I only have two computers here! it works out for me! I hope this sample helps someone out !!!!

Sample Code

clsComputerNetworks.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;

namespace getComputerNetworkNames
{
    /// 
    /// for micorosoft's documentation
    /// http://msdn.microsoft.com/en-us/library/aa370623(VS.85).aspx
    /// another helpful site
    /// http://www.pinvoke.net/default.aspx/netapi32.netserverenum
    /// http://win32.mvps.org/index.html
    /// when i searched in google i found this good article at codeproject
    /// http://www.codeproject.com/KB/IP/ListNetworkComputers.aspx 
    /// 
    public class clsComputerNetworks
    {
        #region constants

        public const uint ERROR_SUCCESS        = 0;
        public const uint ERROR_MORE_DATA    = 234;
        public enum SV_101_TYPES:uint
        {
            SV_TYPE_WORKSTATION= 0x00000001,
            SV_TYPE_SERVER= 0x00000002,
            SV_TYPE_SQLSERVER = 0x00000004,
            SV_TYPE_DOMAIN_CTRL= 0x00000008,
            SV_TYPE_DOMAIN_BAKCTRL= 0x00000010,
            SV_TYPE_TIME_SOURCE= 0x00000020,
            SV_TYPE_AFP= 0x00000040,
            SV_TYPE_NOVELL= 0x00000080,
            SV_TYPE_DOMAIN_MEMBER = 0x00000100,
            SV_TYPE_PRINTQ_SERVER = 0x00000200,
            SV_TYPE_DIALIN_SERVER = 0x00000400,
            SV_TYPE_XENIX_SERVER = 0x00000800,
            SV_TYPE_SERVER_UNIX = 0x00000800,
            SV_TYPE_NT = 0x00001000,
            SV_TYPE_WFW = 0x00002000,
            SV_TYPE_SERVER_MFPN= 0x00004000,
            SV_TYPE_SERVER_NT = 0x00008000,
            SV_TYPE_POTENTIAL_BROWSER = 0x00010000,
            SV_TYPE_BACKUP_BROWSER= 0x00020000,
            SV_TYPE_MASTER_BROWSER= 0x00040000,
            SV_TYPE_DOMAIN_MASTER = 0x00080000,
            SV_TYPE_SERVER_OSF= 0x00100000,
            SV_TYPE_SERVER_VMS= 0x00200000,
            SV_TYPE_WINDOWS= 0x00400000, 
            SV_TYPE_DFS= 0x00800000, 
            SV_TYPE_CLUSTER_NT= 0x01000000, 
            SV_TYPE_TERMINALSERVER= 0x02000000, 
            SV_TYPE_CLUSTER_VS_NT = 0x04000000, 
            SV_TYPE_DCE= 0x10000000, 
            SV_TYPE_ALTERNATE_XPORT= 0x20000000, 
            SV_TYPE_LOCAL_LIST_ONLY= 0x40000000, 
            SV_TYPE_DOMAIN_ENUM= 0x80000000,
            SV_TYPE_ALL= 0xFFFFFFFF 
        };

        #endregion 
        
        [StructLayout(LayoutKind.Sequential)]
        public struct _SERVER_INFO_100
        {
            internal int sv100_platform_id;
            [MarshalAs(UnmanagedType.LPWStr)]
            internal string sv100_name;
        }

        [DllImport("netapi32.dll", CharSet = CharSet.Auto, EntryPoint = "NetServerEnum", SetLastError = true)]
        public static extern int NetServerEnum([MarshalAs(UnmanagedType.LPWStr)]string servername,
        int level,
        out IntPtr bufptr,
        int prefmaxlen,
        ref int entriesread,
        ref int totalentries,
        SV_101_TYPES servertype,
        [MarshalAs(UnmanagedType.LPWStr)]string domain,
        IntPtr resume_handle);

        [DllImport("netapi32.dll", EntryPoint = "NetApiBufferFree")]
        public static extern int NetApiBufferFree(IntPtr buffer);

        private static IntPtr bufferRecData = IntPtr.Zero;
        private static IntPtr Buffer_ = IntPtr.Zero;
        private static int entriesEnumerated = 0;
        private static int totalComputersInNetwork = 0;
        private static IntPtr resHandle = IntPtr.Zero;
        private static int sizeofINFO = Marshal.SizeOf(typeof(_SERVER_INFO_100));

        public static List<string> getNetworkComputers()
        {
            List<string> networkComputers = new List<string>();

            try
            {
                int ret = NetServerEnum(null, 100, out bufferRecData,
                    -1,
                    ref entriesEnumerated,
                    ref totalComputersInNetwork, 
                    SV_101_TYPES.SV_TYPE_WORKSTATION | SV_101_TYPES.SV_TYPE_SERVER, 
                    null,  
                    resHandle);

                if (ret == 0)
                {
                    for (int intCounter = 0; intCounter < totalComputersInNetwork; intCounter++)
                    {
                       Buffer_ = new IntPtr((int)bufferRecData +
                                   (intCounter * sizeofINFO));
                   
                        _SERVER_INFO_100 svrInfo = (_SERVER_INFO_100)
                            Marshal.PtrToStructure(Buffer_,
                                    typeof(_SERVER_INFO_100));


                        networkComputers.Add(svrInfo.sv100_name);
                    }
                }
            }
            catch (Exception ex)
            {
                throw;
            }
            finally
            {
                NetApiBufferFree(bufferRecData);
            }

            return networkComputers;
        }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace getComputerNetworkNames
{
    public partial class frmComputerName : Form
    {
        public frmComputerName()
        {
            InitializeComponent();
        }


        private void btnGetComputerName_Click(object sender, EventArgs e)
        {
            try
            {
                if (this.lstComputerName.Items.Count > 0)
                    this.lstComputerName.Items.Clear();

                
                List ComputerName = clsComputerNetworks.getNetworkComputers();

                foreach (string name in ComputerName)
                {
                    this.lstComputerName .Items.Add(name);
                }

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }

        }
    }
}

DataBinding Part 2(Navigation with Data Binding)

2010-10-19T00:00:00.001+08:00

please refer to the first part of this sample

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace DataBinding
{
    public partial class Form2 : Form
    {

        private DataTable dt = null;
        private BindingManagerBase storeBinding;

        public Form2()
        {
            InitializeComponent();

            this.dt = clsInstance.Products.getProducts();

            this.txtProductID.DataBindings.Add("Text" , dt, "ProductID");
            this.txtProductName.DataBindings.Add("Text", dt, "ProductName");
            this.txtProductPrice.DataBindings.Add("Text", dt, "ProductPrice");

            this.storeBinding = this.BindingContext[dt];
            
            this.storeBinding.PositionChanged += new EventHandler(storeBinding_PositionChanged);
        }

        private void storeBinding_PositionChanged(object sender, EventArgs e)
        {
            int intRow = 1 + storeBinding.Position;

            this.lblCurrentRow.Text = string.Format("{0} of {1}", intRow, storeBinding.Count);

        }

        private void btnPrevious_Click(object sender, EventArgs e)
        {
            if (storeBinding.Position > 0)
                storeBinding.Position -= 1;
            else
                storeBinding.Position = storeBinding.Count-1; 
        }

        private void btnNext_Click(object sender, EventArgs e)
        {
            if (storeBinding.Position != storeBinding.Count - 1)
                storeBinding.Position += 1;
            else
                storeBinding.Position = 0;
        }
    }
}

DataBinding Part 1

2010-10-18T23:48:00.001+08:00

Binding to a list control is one of the most common task. I think most of the .NET list controls has a DataSource property in which accepts reference to any datasource(IList).

In our example I used MSACCESS for our backend database for simplicity.
This will be our example data for the rest of the databinding samples!

Sample screenshot of the application!

App.config

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
 <connectionStrings>
  <add providerName="System.Data.OleDb" 
    name="MyConnectionString" 
    connectionString=
    "Provider= Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\SampleDB.accdb;User Id=admin;Password=;"/>
 </connectionStrings>
</configuration>

To use ConfigurationManager, please add System.Configuration to your references.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Data.OleDb;
using System.Configuration;

namespace DataBinding
{
    public class clsGetData
    {
        public DataTable getProducts()
        {
            DataSet ds = new DataSet();

            using(OleDbConnection cn = new OleDbConnection 
                (ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString))
            {
                using (OleDbCommand cmd = new OleDbCommand("SELECT * FROM tblSampleProducts", cn))
                {
                    using (OleDbDataAdapter adptr = new OleDbDataAdapter(cmd))
                    {
                        adptr.Fill(ds, "tblProducts");
                    }
                }
            }

            return ds.Tables["tblProducts"];
        }
    }
}

clsInstance.cs < i created this class for single instance of clsGetData

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;

namespace DataBinding
{
    public class clsInstance
    {
        private static readonly clsGetData getData = new clsGetData();

        public static clsGetData Products
        { 
            get { return getData; }
        }
    }
}

Form1.cs

namespace DataBinding
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void btnBind_Click(object sender, EventArgs e)
        {
            this.lstProducts.DataSource = clsInstance.Products.getProducts();
            this.lstProducts.ValueMember = "ProductID";
            this.lstProducts.DisplayMember = "ProductName";
        }

        private void btnBindDataView_Click(object sender, EventArgs e)
        {
            DataTable dt = clsInstance.Products.getProducts();
            
            dt.DefaultView.RowFilter = "ProductPrice < 1000";

            this.lstProducts.DataSource = dt;
            this.lstProducts.ValueMember = "ProductID";
            this.lstProducts.DisplayMember = "ProductName";
        }
    }
}

Inputbox C#

2010-10-16T23:44:00.001+08:00

Many vb/vb.net developers are used with the InpuBox(it displays a prompt and waits for the user to input text then returns a string containing the contents of the text box).....
In using C# InputBox is not available!!!! so i decided to create one.
So i might help someone who needs this kind of functionality!

clsInputBox.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Drawing;

namespace InputBoxCS
{
    public class clsInputBox
    {
        private static Form frmInputBox = new Form();
        private static Label lblPrompt = new Label();
        private static Button btnOk = new Button();
        private static Button btnCancel = new Button();
        private static TextBox txtResponse = new TextBox();
        

        /// 
        /// Initialize the controls
        /// 
        static clsInputBox()
        {
      
            frmInputBox.StartPosition = FormStartPosition.CenterScreen;
            frmInputBox.MinimizeBox = false;
            frmInputBox.MaximizeBox = false;
            frmInputBox.FormBorderStyle = FormBorderStyle.FixedDialog;

            frmInputBox.Controls.AddRange(new Control[] { lblPrompt , btnOk , btnCancel, txtResponse});
            frmInputBox.Size = new Size(346, 130);
            frmInputBox.AcceptButton = btnOk;
            frmInputBox.CancelButton = btnCancel;


            btnOk.Size = new Size(50, 23);
            btnOk.Location = new Point(278, 4);

            btnCancel.Size = new Size(50, 23);
            btnCancel.Location = new Point(278, 33);

            lblPrompt.AutoSize = true;
            lblPrompt.Location = new Point(12, 14);

            txtResponse.Size = new Size(316, 20);
            txtResponse.Location = new Point(12, 62);
        }

        public static DialogResult Show (string Prompt, string title, string defaultresponse, ref string value )
        {
            frmInputBox.Text = title;
            lblPrompt.Text = Prompt;
            btnOk.Text = "&OK";
            btnCancel.Text = "&Cancel";
            btnOk.DialogResult = DialogResult.OK;
            btnCancel.DialogResult = DialogResult.Cancel;

            txtResponse.Focus();

            DialogResult result = frmInputBox.ShowDialog();
            value = txtResponse.Text;

            return result;

        }
    }
}

Form1.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;


namespace InputBoxCS
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button3_Click(object sender, EventArgs e)
        {
            string value  = "";

            if (DialogResult.OK == InputBoxCS.clsInputBox.Show("this my prompt", "this is my title", "response", ref value))
            {
                MessageBox.Show(value);
            }
        }
    }
}

Get Running Process C#

2010-10-04T09:42:00.001+08:00

If you want to access local computer process this might get you started! In this example i used a windows form with a listview and imagelist. Nothing fancy just a simple application that might help you started with System.Diagnostics.Process check Microsoft's documentation click here

Form1.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Diagnostics;

namespace GetRunningProcess
{
    public partial class frmGetProcess : Form
    {
        public frmGetProcess()
        {
            InitializeComponent();
        }

        private void SetupListView()
        {
            this.listView1.Items.Clear();
            this.listView1.View = View.Tile ;
            this.listView1.LargeImageList = this.imageList1;
            this.listView1.Columns.Add("Image Name", 100, HorizontalAlignment.Left);
        
        }

        private void frmGetProcess_Load(object sender, EventArgs e)
        {
            SetupListView();

            this.listView1.BeginUpdate();

            Process[] proc = Process.GetProcesses();

            foreach (Process proc_ in proc)
            {
                ListViewItem item = new ListViewItem(proc_.ProcessName);
             
                this.listView1.Items.Add(item);
                item.ImageIndex = 0;
            }

            this.listView1.EndUpdate();
        }
    }
}

Form1.Designer.cs

namespace GetRunningProcess
{
    partial class frmGetProcess
    {
        /// 
        /// Required designer variable.
        /// 
        private System.ComponentModel.IContainer components = null;

        /// 
        /// Clean up any resources being used.
        /// 
        /// true if managed resources should be disposed; otherwise, false.        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code

        /// 
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// 
        private void InitializeComponent()
        {
            this.components = new System.ComponentModel.Container();
            System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(frmGetProcess));
            this.listView1 = new System.Windows.Forms.ListView();
            this.imageList1 = new System.Windows.Forms.ImageList(this.components);
            this.SuspendLayout();
            // 
            // listView1
            // 
            this.listView1.Dock = System.Windows.Forms.DockStyle.Fill;
            this.listView1.Location = new System.Drawing.Point(0, 0);
            this.listView1.Name = "listView1";
            this.listView1.Size = new System.Drawing.Size(394, 415);
            this.listView1.TabIndex = 0;
            this.listView1.UseCompatibleStateImageBehavior = false;
            // 
            // imageList1
            // 
            this.imageList1.ImageStream = ((System.Windows.Forms.ImageListStreamer)(resources.GetObject("imageList1.ImageStream")));
            this.imageList1.TransparentColor = System.Drawing.Color.Transparent;
            this.imageList1.Images.SetKeyName(0, "icon_process.ico");
            // 
            // frmGetProcess
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(394, 415);
            this.Controls.Add(this.listView1);
            this.Name = "frmGetProcess";
            this.Text = "Get Running Process";
            this.Load += new System.EventHandler(this.frmGetProcess_Load);
            this.ResumeLayout(false);

        }

        #endregion

        private System.Windows.Forms.ListView listView1;
        private System.Windows.Forms.ImageList imageList1;
    }
}

Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;

namespace GetRunningProcess
{
    static class Program
    {
        /// 
        /// The main entry point for the application.
        /// 
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new frmGetProcess());
        }
    }
}

Sample Login C#

2010-10-02T15:56:00.001+08:00

Another sample from me! Just a basic and simple one! I hope someone may benefit from this one! So if you are interested .......

Form1.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.OleDb; 

namespace sampleLogin
{
    public partial class frmLogin : Form
    {
        public frmLogin()
        {
            InitializeComponent();
        }

        private void btnLogin_Click(object sender, EventArgs e)
        {
            using (OleDbConnection cn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=sample.mdb;User Id=admin;Password=;"))
            {
                using (OleDbCommand cmd = new OleDbCommand("SELECT * FROM tblUserAccounts WHERE Username=@Username AND Password_=@Password_", cn))
                {
                    cmd.Parameters.Add("@Username", OleDbType.WChar, 50, "Username").Value = this.txtUsername.Text;

                    cmd.Parameters.Add("@Password_", OleDbType.WChar, 50, "Password_").Value = this.txtPassword.Text;

                    if (cn.State == ConnectionState.Closed)
                    {
                        cn.Open();
                        
                        using (OleDbDataReader rdr = cmd.ExecuteReader())
                        {
                            if (rdr.HasRows)
                            {
                                rdr.Read();

                                if ((rdr.GetString(0).Equals(this.txtUsername.Text)) && (rdr.GetString(1).Equals(this.txtPassword.Text)))
                                {
                                    MessageBox.Show("Login Succesful"); 
                                }
                            
                            }
                        }
                    }
                }
            }
        }
    }
}

Form1.Designer.cs

namespace sampleLogin
{
    partial class frmLogin
    {
        /// 
        /// Required designer variable.
        /// 
        private System.ComponentModel.IContainer components = null;

        /// 
        /// Clean up any resources being used.
        /// 
        /// true if managed resources should be disposed; otherwise, false.protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code

        /// 
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// 
        private void InitializeComponent()
        {
            this.btnLogin = new System.Windows.Forms.Button();
            this.txtUsername = new System.Windows.Forms.TextBox();
            this.txtPassword = new System.Windows.Forms.TextBox();
            this.lblUsername = new System.Windows.Forms.Label();
            this.lblPassword = new System.Windows.Forms.Label();
            this.SuspendLayout();
            // 
            // btnLogin
            // 
            this.btnLogin.Location = new System.Drawing.Point(88, 81);
            this.btnLogin.Name = "btnLogin";
            this.btnLogin.Size = new System.Drawing.Size(235, 23);
            this.btnLogin.TabIndex = 0;
            this.btnLogin.Text = "Login";
            this.btnLogin.UseVisualStyleBackColor = true;
            this.btnLogin.Click += new System.EventHandler(this.btnLogin_Click);
            // 
            // txtUsername
            // 
            this.txtUsername.Location = new System.Drawing.Point(88, 6);
            this.txtUsername.Name = "txtUsername";
            this.txtUsername.Size = new System.Drawing.Size(235, 20);
            this.txtUsername.TabIndex = 2;
            // 
            // txtPassword
            // 
            this.txtPassword.Location = new System.Drawing.Point(88, 45);
            this.txtPassword.Name = "txtPassword";
            this.txtPassword.Size = new System.Drawing.Size(235, 20);
            this.txtPassword.TabIndex = 3;
            // 
            // lblUsername
            // 
            this.lblUsername.AutoSize = true;
            this.lblUsername.Location = new System.Drawing.Point(12, 9);
            this.lblUsername.Name = "lblUsername";
            this.lblUsername.Size = new System.Drawing.Size(58, 13);
            this.lblUsername.TabIndex = 4;
            this.lblUsername.Text = "Username:";
            // 
            // lblPassword
            // 
            this.lblPassword.AutoSize = true;
            this.lblPassword.Location = new System.Drawing.Point(12, 45);
            this.lblPassword.Name = "lblPassword";
            this.lblPassword.Size = new System.Drawing.Size(56, 13);
            this.lblPassword.TabIndex = 5;
            this.lblPassword.Text = "Password:";
            // 
            // frmLogin
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(330, 118);
            this.Controls.Add(this.lblPassword);
            this.Controls.Add(this.lblUsername);
            this.Controls.Add(this.txtPassword);
            this.Controls.Add(this.txtUsername);
            this.Controls.Add(this.btnLogin);
            this.Name = "frmLogin";
            this.Text = "Sample Login";
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private System.Windows.Forms.Button btnLogin;
        private System.Windows.Forms.TextBox txtUsername;
        private System.Windows.Forms.TextBox txtPassword;
        private System.Windows.Forms.Label lblUsername;
        private System.Windows.Forms.Label lblPassword;
    }
}

Terminate a process using C#

2010-10-02T14:48:00.001+08:00

Sometimes in our application we need to terminate a process or a service.
In our example i'll be terminating a notepad. However, in some books that I have read
for windows-based applications,call Process.CloseMainWindow to send close message to the applications main window.If ever the windows-based application ignored Process.CloseMainWindow, or non-windows application, call the Process.Kill method.

Sample output

lets check the sample code ......

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Threading;
 
namespace TerminateAProcessCS
{
    class Program
    {
        static void Main(string[] args)
        {

            bool processBol = false;

            string processName = "";

            while (!processBol)
            {
                Console.Clear();
                
                Console.WriteLine("Please enter the name process name to be killed: ");

                processName = Console.ReadLine();

                if (!string.IsNullOrEmpty(processName))
                {
                    Process[] proc = Process.GetProcesses();

                    foreach (Process proc_ in proc)
                    {
                        if (proc_.ProcessName.Equals(processName))
                        {

                            Console.WriteLine("Get some information before killing the process .... ");
   
                            Console.WriteLine("Proces Name: {0}: ", proc_.ProcessName);
                            
                            Console.WriteLine("Privilige: {0}", proc_.PrivilegedProcessorTime);
                         
                            Console.WriteLine("Please wait.....");
                            
                            System.Threading.Thread.Sleep(5000);

                            proc_.Kill();

                            if (proc_.HasExited)
                            {

                                Console.WriteLine("{0} exited! ", proc_.ProcessName);
                                Console.WriteLine("Started Time: {0}", proc_.StartTime);
                                Console.WriteLine("Exit Time: {0}", DateTime.Now ); 
                            }

                            Console.WriteLine("Do you want to try again [y/n] ?");

                            string strRes = Console.ReadLine();

                            if ((strRes.Equals("n")) || (!strRes.Equals("N")))
                            {
                                processBol = true;
                            }

                            break;
                        }
                    }
                }
            }

            Console.WriteLine("Press any key to exit");
            Console.ReadLine();
        }
    }
}

Detect network card or adapter, changes in C#

2010-10-02T13:28:00.001+08:00

In this example, we are going to check the Sysetm.Net.NetworkInformation.NetworkChange Class to have the mechanism to check whether changes to network occurs during the life of your application. Occurding to microsoft's documentation add handlers to NetworkAddressChanged and NetworkAvailabilityChanges events.

Sample output

so lets check the code snippet

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net.NetworkInformation; 

namespace DetectNetworkChangesCS
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("This sample program will detect network changes in a local computer");
 
            NetworkChange.NetworkAvailabilityChanged += new NetworkAvailabilityChangedEventHandler(NetworkChange_NetworkAvailabilityChanged);
            
            NetworkChange.NetworkAddressChanged += new NetworkAddressChangedEventHandler(NetworkChange_NetworkAddressChanged);
            
           

            Console.Read();
        }

        static void NetworkChange_NetworkAvailabilityChanged(object sender, NetworkAvailabilityEventArgs e)
        {
            if (e.IsAvailable)
            {
                Console.WriteLine("Network is available");
            }
            else
            {
                Console.WriteLine("Network is not available");
            }
        }

        static void NetworkChange_NetworkAddressChanged(object sender, EventArgs e)
        {
            try
            {
                //check to see if network is available
                if (NetworkInterface.GetIsNetworkAvailable())
                {

                    NetworkInterface[] @interface = NetworkInterface.GetAllNetworkInterfaces();

                    foreach (NetworkInterface face in @interface)
                    {
                        if (face.NetworkInterfaceType == NetworkInterfaceType.Ethernet)
                        {
                            Console.WriteLine(face.Name); 
    
                            UnicastIPAddressInformationCollection ip = face.GetIPProperties().UnicastAddresses;

                            foreach (UnicastIPAddressInformation ipp in ip)
                            {
                                Console.WriteLine("Valid Lifetime: {0}", ipp.AddressValidLifetime);
                                Console.WriteLine("Preferred Lifetime: {0}", ipp.AddressPreferredLifetime);
                            }

                            Console.WriteLine("===============================================================");

                        }
                    }

                }

            }
            catch (NetworkInformationException ex)
            {
                Console.WriteLine(ex.Message);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
        }
    }
}

Obtain Local Network Interface using C#

2010-09-25T14:40:00.001+08:00

As a developer, sometimes you need to obtain about the network adapters and network config of your local machine..... so i created a simple code snippets that might help somebody!!!

for simplicity I only checked for Ethernet interface only.... so let's check it out

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.NetworkInformation;

namespace LanInterface
{
    class Program
    {
        static void Main(string[] args)
        {

            // as shown above we used System.Net.NetworkInformation namespace so could use some of its classes

            //lets check for network availability
            bool bolNetworkAvailable = NetworkInterface.GetIsNetworkAvailable();

            try
            {
                if (bolNetworkAvailable)
                {

                    //lets get all of the Network Interface for the current machine

                    NetworkInterface[] interfaces = NetworkInterface.GetAllNetworkInterfaces();

                    foreach (NetworkInterface ints in interfaces)
                    {
                        // lets output to the screen some of the basic information!

                        //lets only focus on Ethernet type only for simplicity
                        if (ints.NetworkInterfaceType == NetworkInterfaceType.Ethernet)
                        {

                            Console.WriteLine("Network ID: {0}", ints.Id);
                            Console.WriteLine("Network Name: {0}", ints.Name);
                            Console.WriteLine("Network Type: {0}", ints.NetworkInterfaceType);
                            Console.WriteLine("Network Description: {0}", ints.Description);
                            Console.WriteLine("Network Status: {0}", ints.OperationalStatus);
                            Console.WriteLine("Network Speed: {0}", ints.Speed);

                            //lets get the physical address

                            Console.WriteLine("Network MAC Address {0}", ints.GetPhysicalAddress().ToString());
                           
                            //lets get the network statistics

                            Console.WriteLine("Bytes Send: {0}", ints.GetIPv4Statistics().BytesSent);
                            Console.WriteLine("Bytes Received: {0}", ints.GetIPv4Statistics().BytesReceived);


                            Console.WriteLine("\r\n");

                        }
                    }
                }
                else
                {
                    Console.WriteLine("NIC or LAN not available");
                }
            }
            catch (NetworkInformationException ex)
            {
                Console.WriteLine(ex.Message);
            }
           
            Console.ReadLine();
        }
    }
}

Backup SQL c#

2010-08-28T21:50:00.001+08:00

This sample application will teach how to backup a SQL database to a BAK file using C#. I hope someone will benefit from this.

ScreenShot

First we should add reference from our project see the images below,

After clicking the "Add Reference" a dialog box will pop up look for the MicrosoftSQLDMO Object Library, see the images below,

After doing the steps above your good to go!

i created a file name: clsBackupDemo.cs
inside this class we have two static methods

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using SQLDMO;

namespace sqlBackup
{
    class clsBackupDemo
    {
        /// 
        /// Gets and returns all the SQLServer Instances install on your computer
        /// 
        public static List<string> ListOfServerNames()
        {
            List<string> sqlNames = new List<string>();

            SQLDMO.NameList sqlsrvrName = null;
            SQLDMO.Application  sqlsrvrApp = new SQLDMO.Application ();

            sqlsrvrName = sqlsrvrApp.ListAvailableSQLServers();

            for (int i = 0; i < sqlsrvrName.Count; i++)
            {
               sqlNames.Add(sqlsrvrName.Item(i + 1));
          
            }
  
            return sqlNames;
        
        }

         /// 
        /// connects and gets all the database of the sql server instances
        ///   selected    by the user
        /// 
        public static List<string> GetDatabase(string SqlServerName , 
                              string   Username_ , string Password_)
        {
            List<string> strDatabase = new List<string>();

            SQLDMO.SQLServer srvrToConnect = new SQLDMO.SQLServer();

            srvrToConnect.Connect(SqlServerName, Username_, Password_);

            foreach(SQLDMO.Database db in srvrToConnect.Databases)
            {
                strDatabase.Add(db.Name.ToString());

            }

            return strDatabase;

        }

    }
}

now I also created a form
filename: frmBackup.cs so user can interact with the sample application

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using SQLDMO;

namespace sqlBackup
{
    public partial class frmBackup : Form
    {
        public frmBackup()
        {
            InitializeComponent();
        }

       private enum BackUpType:int { 
        
            CompleteBackup,
            DifferentialBackup
       }

       private BackUpType BackupType_;

        #region GetSQLInstances

        private void GetSQLInstancesNames()
        {
            List<string> listOfSQLInstances;

            listOfSQLInstances = clsBackupDemo.ListOfServerNames();

            if (listOfSQLInstances.Count == 0)
            {
                cmbServer.Text = "[No server found]";

            }

            else
            {
                foreach (string names in listOfSQLInstances)
                {
                    this.cmbServer.Items.Add(names);

                }

                this.cmbServer.SelectedIndex = 0;
            }
        
        }

        #endregion

        #region ConnecttoSQLAndGetDatabases

        private void Connect()
        {
            try
            {
                List<string> strDB = clsBackupDemo.GetDatabase(this.cmbServer.SelectedItem.ToString(), this.txtUsername.Text, this.txtPassword.Text);

                if (strDB.Count == 0)
                {
                    this.cmbDatabase.Text = "No database found";
                }
                else
                {
                    foreach (string db in strDB)
                    {
                        this.cmbDatabase.Items.Add(db); 
                    
                    }
                
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message); 
            }
        }

        #endregion 

        private void frmBackup_Load(object sender, EventArgs e)
        {
            GetSQLInstancesNames();
        }

        private void btnConnect_Click(object sender, EventArgs e)
        {
            Connect();
        }

        private void btnBrowse_Click(object sender, EventArgs e)
        {
            FolderBrowserDialog dlg = new FolderBrowserDialog();

            dlg.Description = "SQL Server Backup";
            dlg.RootFolder = Environment.SpecialFolder.Desktop;
            dlg.ShowNewFolderButton = true;
            
            if (dlg.ShowDialog() == DialogResult.OK)
            {
                string getDBSelected = @"\" + this.cmbDatabase.SelectedItem.ToString();

                this.txtPath.Text = dlg.SelectedPath + getDBSelected + ".bak";
            }


        }

        private void btnBackup_Click(object sender, EventArgs e)
        {
            //backup

            SQLDMO.SQLServer srvrToConnect = new SQLDMO.SQLServer();

            srvrToConnect.Connect(this.cmbServer.SelectedItem.ToString (), txtUsername.Text , txtPassword.Text );


            SQLDMO.Backup bckp = new SQLDMO.Backup();

            if (this.BackupType_ == BackUpType.CompleteBackup)
            {
                bckp.Action = SQLDMO_BACKUP_TYPE.SQLDMOBackup_Database;  
            }
            else if (this.BackupType_ == BackUpType.DifferentialBackup)
            {
                bckp.Action = SQLDMO_BACKUP_TYPE.SQLDMOBackup_Differential;
            }
            
            bckp.PercentComplete += new BackupSink_PercentCompleteEventHandler(bckp_PercentComplete);
            
            bckp.Complete += new BackupSink_CompleteEventHandler(bckp_Complete);
            
            bckp.Database = this.cmbDatabase.SelectedItem.ToString();

            bckp.Files = this.txtPath.Text;

            bckp.SQLBackup(srvrToConnect);

            bckp_Complete("Complete");

        }

        void bckp_PercentComplete(string Message, int Percent)
        {
            System.Threading.Thread.Sleep(100);

            prgBAckup.Value = Percent;

            System.Windows.Forms.Application.DoEvents();
        }

        private void  bckp_Complete(string Message)
        {
            MessageBox.Show(Message); 
        }

        private void rbtnCompleteBackup_CheckedChanged(object sender, EventArgs e)
        {
            RadioButton rbtn = (RadioButton)sender;

            if (object.ReferenceEquals (rbtn, this.rbtnCompleteBackup))
            {
                BackupType_ = BackUpType.CompleteBackup;
            }
            else if (object.ReferenceEquals(rbtn, rbtnDifferentialBackup))
            {
                BackupType_ = BackUpType.DifferentialBackup;
            }
        }

    }
}

c# Array Part 2 (Using reference types)

2010-08-12T13:33:00.001+08:00

Using arrays in c#, you can also declare arrays of custom types. In our example let’s start with a Customer class, having two constructors, 3 properties (FirstName, LastName, ContactNumber), and an override of ToString() method of the Object class.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ArraysPart2cs
{
    class Customer
    {
        #region -[Private Member Fields]-

        private string FirstName_;
        private string LastName_;
        private string ContactNumber_;

        #endregion 

        //our first constructor
        public Customer()
        { 
        
        }
        //our second constructor
        public Customer(string _FirstName, string _LastName, string _ContactNumber)
        {
            this.FirstName_ = _FirstName;
            this.LastName_ = _LastName;
            this.ContactNumber_ = _ContactNumber;
        }

        #region -[Properties]-

        public string FirstName
        {
            get { return this.FirstName_; }
            set { this.FirstName_ = value; }
        }

        public string LastName
        {
            get { return this.LastName_; }
            set { this.LastName_ = value; }
        }

        public string ContactNumber
        {
            get { return this.ContactNumber_; }
            set { this.ContactNumber_ = value; }
        }

        #endregion 
       
        public override string ToString()
        {
            string FullName = string.Concat(this.LastName_, " ", this.FirstName_);

            return string.Format("You are : {0}, your contact number: {1}", FullName, this.ContactNumber_);

        }
    }
}

Inside our main method, let’s try to use our custom type with arrays.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ArraysPart2cs
{
    class Program
    {
        static void Main(string[] args)
        {

            Console.Title = "Arrays Part 2";

           //so lets declare an array of customer having 2 elements

            Customer[] customer = new Customer[2];

            //lets try a short method 

            customer[0] = new Customer("John Felix", "Cruz", "+639083069011");

            Console.WriteLine(customer[0].ToString());

            //lets try a long method 

            customer[1] = new Customer();

            customer[1].FirstName = "Jin";
            customer[1].LastName = "Zalzos";
            customer[1].ContactNumber = "+639083069011";

            Console.WriteLine(customer[1].ToString());

    
            //you may also use array initializer with custom types

            Customer[] anotherCustomer = {new Customer("Rhian","Calzado","+63908306911"),
                                          new Customer("B. Togie", "Calzado", "+6301233655")};

            Console.WriteLine(anotherCustomer[0]);

            Console.ReadKey();

        }
    }
}

c# Array Part I

2010-08-05T22:47:00.001+08:00

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ArraysPartOne
{
    class Program
    {
        static void Main(string[] args)
        {
            /*
             * sometimes programmers needs to use 
             * multiple objects of the same type(value types or reference types) 
             * so we use arrays.
             * Definition of array -> is a data structure that contains a number of 
             * elements of the same type. (Professional C# 2008 Wrox)
             */

            /*
             * how to declare an array?
             * so there are many ways on how to declare an array
             * just try to look below
             */

            int[] _FirstArray = new int[5];

            int[] _SecondArray = new int[2] {4,5};

            int[] _ThirdArray = new int[] { 4, 5, 6 };

            int[] _FourthArray = { 6,7,8};

            // end of declaring or initilizing an array

            //start of our sample array
            try
            {

                Console.WriteLine("Array Sample Part I");

                int intInputNumber =0;
                int intCounter =0;

                Console.WriteLine("How many number to want to input");
                
          
                intInputNumber = int.Parse (Console.ReadLine());
                
                int [] _UserArray = new int[intInputNumber];

               
               
                do
                {
                    Console.WriteLine(
                    string.Format
                   ("Input numbers at index[{0}]",intCounter ));

                    _UserArray[intCounter] = int.Parse(Console.ReadLine());

                    intCounter++;
                
                }while (intCounter < intInputNumber);


                //iterate throught the elements in the array ,
               //i'll be using for and foreach loop

                Console.WriteLine("Iterate elements using for loop");

                for (int i = 0; 
                         i < _UserArray.Length; i++)
                {
                    string strMessage = 
                    string.Format
                   ("Array Index [{0}] = [{1}]", i, _UserArray[i]);
                    
                    Console.WriteLine(strMessage + Environment.NewLine);
                }

                Console.WriteLine("Iterate elements using foreach loop");

                StringBuilder result = new StringBuilder();

                foreach (int IndexValue in _UserArray)
                {
                    result.Append(IndexValue);
                    result.Append(",");
                }

                Console.WriteLine(result);

                Console.WriteLine("Do you want to sort the array?[y/n]");

                string ans = Console.ReadLine();

                if (ans.ToUpper().Equals("Y"))
                {
                    Array.Sort(_UserArray);
                
                }

                //iterate throught the elements 
               //in the array ,i'll be using for and foreach loop

                Console.WriteLine("Iterate elements using for loop");

                for (int i = 0; i < _UserArray.Length; i++)
                {
                    string strMessage = 
                    string.Format
                    ("Array Index [{0}] = [{1}]",
                                    i, _UserArray[i]);

                    Console.WriteLine
                    (strMessage + Environment.NewLine);
                }

                Console.ReadKey();

            }
            //if you are a wrong index value, 
            //IndexOutOfRangeException will be thrown
            
            catch (IndexOutOfRangeException ex)
            {
                Console.WriteLine(ex.Message);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            
            }
        }
    }
}

MDI (Multiple Document Interface) Set Background Image

2010-06-30T15:10:00.001+08:00

MDI (Multiple Document Interface) Set Background Image

To change the background color of a parent MDI form is to set the background color property. However, it seems to ignore it. Also some of us hate the dark gray background.

In this tutorial I will help you to programmatically set the Background Image of the MDI parent. This includes vs2003 & vs2005 c# source file.

First we set the Form property ISMDICONTAINER = TRUE

VS2003 C#

private System.Windows.Forms.MainMenu mainMenu1;
private System.Windows.Forms.MenuItem menuItem1;
private System.Windows.Forms.MenuItem menuItem2;

private string filepath = System.Environment.CurrentDirectory; 

private void Form1_Load(object sender, System.EventArgs e)
{
			
filepath = System.IO.Path.Combine (filepath, "Desert.jpg");

 foreach(Control cntrl in this.Controls) 
 {
	if ((cntrl.GetType() == typeof(System.Windows.Forms.MdiClient ))){
					
	     cntrl.BackgroundImage = Image.FromFile(filepath);
				}
 }
}

private void menuItem2_Click(object sender, System.EventArgs e)
{	
	Form frmChild = new Form();

	frmChild.MdiParent = this;
	frmChild.Text = "Hello, im a child form";
	frmChild.Show ();

}

VS2005 C# - applicable to VS2008

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace MdiApplicationCS2005
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            foreach (Control cntrl in this.Controls)
            {
                if (cntrl is MdiClient)
                {
                    cntrl.BackgroundImage = Properties.Resources.Jellyfish;  
                }
            }
        }

        private void childToolStripMenuItem_Click(object sender, EventArgs e)
        {
            Form frmChild = new Form();
            frmChild.MdiParent = this;
            frmChild.Text = "Hello i'm a child form";
            frmChild.Show();
        }
    }
}

Recursion C# and VB.Net

2010-06-27T22:39:00.001+08:00

Recursion in C# and VB.Net

Recursion is a procedure (in VB.net) or method (in C#) that calls itself with in the program either directly or indirectly. In other words, a method or procedure is said to be recursive when it contains a statement that calls itself. Moreover, defining looping constructs in these two languages like “while for loops” are used to do repetition.
To really understand, on how to use recursion I will try to give some basic examples. First one will be the Factorial and Fibonacci Series both languages will be used on this tutorial. So let’s get started.

Sample codes goes here:

C#

using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;

static class clsMain
{

 private static int Factorial(int intNumber)
 {
        if (intNumber <= 1)
   return 1;
        else 
            return intNumber * Factorial(intNumber - 1);
 }

 private static int Fibonnacci(int intNumber)
 {
        if ((intNumber == 1) | (intNumber == 0)) 
           return intNumber;
        else 
           return Fibonnacci(intNumber - 1) + Fibonnacci(intNumber - 1);
 }


 public static void Main()
 {
      try 
            {
       Console.WriteLine("Welcome to Recursion");

       Console.WriteLine("---------------------");

       Console.WriteLine("Our example Factorial Program and Fibonacci");

       Console.WriteLine("---------------------");

       Console.WriteLine("Enter number to get factorial");

                int intNumber = int.Parse (Console.ReadLine());

       string factorialAnswer = null;
       
       factorialAnswer = string.Format("{0}!={1}", intNumber, Factorial(intNumber));
                
                Console.WriteLine(factorialAnswer);
                
                string fibonacciAnswer = null;
                
                fibonacciAnswer = string.Format("Fibonacci Value is {0}", Fibonnacci(intNumber));

                Console.WriteLine(fibonacciAnswer);

                Console.ReadLine();


      } 
            catch (Exception ex) 
            {
                Console.WriteLine(ex.Message);
            }
        }
 }

VB.Net

Option Explicit On
Option Strict On

Module modMain

    Private Function Factorial(ByVal intNumber As Integer) As Integer

        If (intNumber <= 1) Then

            Return 1

        Else

            Return intNumber * Factorial(intNumber - 1)

        End If

    End Function

    Private Function Fibonnacci(ByVal intNumber As Integer) As Integer

        If (intNumber = 1) Or (intNumber = 0) Then

            Return intNumber

        Else

            Return Fibonnacci(intNumber - 1) + Fibonnacci(intNumber - 1)

        End If

    End Function

    Sub Main()

        Try

            Console.WriteLine("Welcome to Recursion")

            Console.WriteLine("---------------------")

            Console.WriteLine("Our example Factorial Program and Fibonacci")

            Console.WriteLine("---------------------")

            Console.WriteLine("Enter number to get factorial")

            Dim intNumber As Integer = Integer.Parse(Console.ReadLine())

            Dim factorialAnswer, fibonacciAnswer As String

            factorialAnswer = String.Format("{0}!={1}", intNumber, Factorial(intNumber))

            Console.WriteLine(factorialAnswer)

            fibonacciAnswer = String.Format("Fibonacci Value is {0}", Fibonnacci(intNumber))

            Console.WriteLine(fibonacciAnswer)

            Console.ReadLine()

        Catch ex As Exception

            Console.WriteLine(ex.Message)

        End Try

    End Sub

End Module

ComboBox AutoComplete

2010-06-20T23:23:00.001+08:00

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace cmbAutoComplete
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private List<string> SampleList()
        {
            List<string> ListToAddinCombobox = new List<string>();

            ListToAddinCombobox.Add("Angeles City");
            ListToAddinCombobox.Add("Baguio City");
            ListToAddinCombobox.Add("Caloocan City");
            ListToAddinCombobox.Add("Davao City");
            ListToAddinCombobox.Add("Malabon City");
            ListToAddinCombobox.Add("Quezon City");
            ListToAddinCombobox.Add("Naga City");
            ListToAddinCombobox.Add("Tacloban City");
            ListToAddinCombobox.Add("Leyte City");
            ListToAddinCombobox.Add("Cebu City");
            ListToAddinCombobox.Add("Dipolog City");
            ListToAddinCombobox.Add("Marikina City");
            ListToAddinCombobox.Add("Navotas City");
            ListToAddinCombobox.Add("Muntinlupa City");
            ListToAddinCombobox.Add("Pasig City");
            ListToAddinCombobox.Add("Las Pinas City");

            ListToAddinCombobox.Sort();

            return ListToAddinCombobox;
        }


        private void Form1_Load(object sender, 
                                  EventArgs e)
        {
            try
            {
              
                this.comboBox1.DataSource = 
                    this.SampleList();
                this.comboBox1.SelectedIndex = -1;

                this.comboBox1.AutoCompleteSource = 
                        AutoCompleteSource.ListItems;

                this.comboBox1.AutoCompleteMode = 
                        AutoCompleteMode.SuggestAppend;
   
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }
    }
}

Local Sql Server Instances using the registry

2010-06-13T15:04:00.001+08:00

vb.net

Option Strict On
Imports Microsoft.Win32
Imports System.Environment

Module modMain
    ''' <summary>
    ''' gets all of the installed 
    ''' instances server of sql 
    ''' </summary>
    ''' <returns>string arrays of sqlserverinstances</returns>
    ''' <remarks>for local servers only</remarks>
    Private Function SqlServerInstances() As String()

        Dim instances As String() = Nothing

        Try

            Dim key As RegistryKey

            key = Registry.LocalMachine. _ 
OpenSubKey("SOFTWARE\Microsoft\MicrosoftSQLServer")

            instances = _ 
                 DirectCast(key. _ 
            GetValue("InstalledInstances"), String())

        Catch ex As Exception

            Console.WriteLine(ex.Message)

        End Try

        Return instances

    End Function

   <stathread()> _
   Sub Main(ByVal args As String())

        If (SqlServerInstances.Count > 0) Then

            For Each sqlElment As String _ 
            In SqlServerInstances()

                Select Case sqlElment

                    Case "MSSQLSERVER"

                        Console.WriteLine _ 
                              (Environment.MachineName)
                    Case Else

                        Dim strSQL As String = _
                        String.Format("{0}\{1}", _ 
                        Environment.MachineName,sqlElment)

                        Console.WriteLine (strSQL)

                End Select

            Next

        End If

    End Sub

End Module

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Win32; 

namespace sqlLocalRegistryCS
{
    class Program
    {
        /// <summary>
        /// gets all of the installed 
        /// instances server of sql 
        /// must be an administrator
        /// </summary>
        /// <returns>string arrays 
        /// of sqlserverinstances</returns>
        /// <remarks>for local servers only </remarks>
        private static  string[] SqlServerInstances()
        {
            string[] instances = null;

            try
            {
                RegistryKey key = default(RegistryKey);

                key = Registry.LocalMachine.
                OpenSubKey
                ("SOFTWARE\\Microsoft\\Microsoft SQL Server");

                instances = 
                (string[])key.GetValue("InstalledInstances");

            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);

            }

            return instances;
        }

        static void Main(string[] args)
        {
            if ((SqlServerInstances().Length  > 0))
                {

                    foreach (string sqlElment 
                    in SqlServerInstances())
                    {
                        switch (sqlElment)
                        {

                            case "MSSQLSERVER":

                                Console.WriteLine
                                (Environment.MachineName);

                                break;
                            
                               default:

                               string strSQL = 
                               string.Format("{0}\\{1}",
                               Environment.MachineName, 
                               sqlElment);

                               Console.WriteLine(strSQL);

                               break;
                        }
                    }
                }
        }
    }
}

Welcome

2010-06-10T03:26:00.000+08:00

Welcome to my blog.
Actually this is my first post, I'm still thinking what programming topics should I write. If you guys have some suggestions please do so. Thanks and enjoy your stay.