How to Dot Net

Validate South African ID Number

2018-05-15T09:21:00.000+02:00

The South African ID Number is a unique number given to every person who is a South African citizen, or who has been granted permanent South African residence. Use this site to find out how the number is made up.

The South African ID Number can be validated using the Luhn algorithm.

I use the following code to validate South African ID Numbers in my applications:

vb.net

Public Shared Function RSA_ID_Number(ByVal id_no As String) As Boolean
        Dim is_valid As Boolean = False

        Try
            If id_no.Length = 13 Then
                Dim intcheck_a As Integer = 0
                Dim strCheck_b As String = ""
                Dim intcheck_b As Integer = 0
                Dim intCheck_c As Integer = 0
                Dim check_calc_result As Integer = 0
                Dim check_digit As Integer = id_no.Substring(12, 1)

                ' Step 1
                For i = 0 To id_no.Length - 1
                    Select Case i
                        Case 0, 2, 4, 6, 8, 10
                            intcheck_a += Convert.ToInt64(id_no.Substring(i, 1))
                        Case 1, 3, 5, 7, 9, 11
                            strCheck_b &= id_no.Substring(i, 1)
                    End Select
                Next

                ' Step 2
                intcheck_b = Convert.ToInt64(strCheck_b) * 2
                strCheck_b = intcheck_b.ToString()

                ' Step 3
                intcheck_b = 0
                For i As Integer = 0 To strCheck_b.Length - 1
                    intcheck_b += Convert.ToInt64(strCheck_b.Substring(i, 1))
                Next

                ' Step 4
                intCheck_c = intcheck_a + intcheck_b

                check_calc_result = 10 - intCheck_c.ToString.Substring(intCheck_c.ToString.Length - 1, 1)

                is_valid = check_calc_result = check_digit
            End If

        Catch ex As Exception : Throw

        End Try

        Return is_valid
    End Function

IIf in javascript/jQuery

2015-11-03T09:33:00.001+02:00

The conditional operator(c#/java/javascript) or IIf(vb), also called an inline if statement, is very useful.

I have used IIF in my vb and c# exploits very often. I wrote a post about the conditional operator for c# here, and it has proven to be very popular.

To use the conditional operator in javasctipt or jQuery is just as simple as using it in c# or vb.

The syntax is: (condition ? first_expression : second_expression);

A simple example is to set a variable based on the condition of another variable:

var animal = 'cat';

var species = (animal == 'cat' ? 'feline' : 'canine');

This snippet checks the variable animal to see if it is set to 'cat'. If the condition is true, species is set to 'feline'. If not, species is set to 'canine'.

Another way to use it would be to set the class of a web page element using the jQuery addClass method:

($("#contactnumber").hasClass("requiredElement") ? "" : $("#contactnumber").addClass("requiredElement"));

This snippet checks the element with an id of contactnumber to see if it has the class requiredElement assigned to it. If it does, then nothing is changed, otherwise the class requiredElement is added to the element.

Please let me know in the comments, if this helped.

Happy coding.

Microsoft Exchange Web Services – Sending an E-Mail

2015-05-07T14:16:00.001+02:00

Before you start find out that comes before this by checking out this post first:
Microsoft Exchange Web Services – First things first

One of the more obvious things that you might want to do with EWS is send an e-mail.

  Dim subject As String = "Your subject"  
  Dim html_Content As String = "<div style=""font-family:Arial;font-size:10pt;color:black"">Insert your html content for your e-mail here</div>"  
  Dim _SendTo As String = "email@address.com"  
   
  Dim replyMessage As New Microsoft.Exchange.WebServices.Data.EmailMessage(_service)  
  replyMessage.Subject = subject  
  replyMessage.Body = html_Content  
  replyMessage.ToRecipients.Add(_SendTo)  
   
  replyMessage.SendAndSaveCopy()

This code snippet will send an e-mail to the address that you specify. Remember to use the code in the post referenced at the top of this post.

More posts about Exchange Web Services will follow.

Please let me know if you found this info helpful.

Microsoft Exchange Web Services – First things first

2015-05-05T10:37:00.001+02:00

Microsoft Exchange Web Services (EWS) allows you to manage your Microsoft Exchange account using built in web services on the Exchange server.
Some of the things EWS allows you to do:

Read mail in any of the folders that your account has access to
Send e-mails from your account
Manage appointments
Move e-mails from one folder to another

The first thing I can recommend is to download and install the Microsoft Exchange Web Services API.

Version 2.2 of the API can be found here:
https://www.microsoft.com/en-us/download/details.aspx?id=42951

Use the following link to find out where your Exchange Web Services are installed, so that you can use the URL as the _service.Url in the code below:
http://blogs.msdn.com/b/deva/archive/2011/12/02/how-to-get-the-ews-endpoint-url-from-outlook-2007-2010.aspx

Once you have the API installed, and you know what the services URL is, you can start a new Visual Studio project, and add Microsoft.Exchange.WebServices.dll as a reference to the project.
In my installation's case it is located in C:\Program Files\Microsoft\Exchange\Web Services\2.2.

You are now ready to get going:

      Private _service As Microsoft.Exchange.WebServices.Data.ExchangeService = New Microsoft.Exchange.WebServices.Data.ExchangeService(Microsoft.Exchange.WebServices.Data.ExchangeVersion.Exchange2010_SP1)  
      Private _serviceCredentials = New Microsoft.Exchange.WebServices.Data.WebCredentials("exchangeUserId", "exchangePassword", "optionalDomainName")  
   
      Private Sub Initiate_EWS_Service()  
           _service.Credentials = _serviceCredentials  
           _service.Url = New Uri("https://exchangeWebServiceURL")  
      End Sub  
   
      Initiate_EWS_Service()

This little bit of code will connect to your Exchange Server and authenticate your supplied credentials. You can use _service to interact with the exchange server account, and perform the functions I mentioned at the beginning of this post.

More posts about Exchange Web Services will follow.

Please let me know if you found this info helpful.

Object doesn't support property or method 'querySelectorAll' - IE9

2013-07-16T13:09:00.003+02:00

I have recently been plagued by an error that I found very difficult to fix.

Object doesn't support property or method 'querySelectorAll'

This error only occurs when using IE9!

There are lots of explanations all over the place on how to fix the problem. Our main problem is that we don’t even use the JavaScript querySelectorAll function, but I suspect that one of the 3^rd party add-ons (Component One) that we use does.

Many solutions just tell you to add to the top of your page, and that will sort things out for you.

What a joke!!! Unfortunately, it is not that simple!

There is more to it, to make it work.

Visual Studio 2010 adds the following to .aspx and .htm pages when you create them:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

This is what works!

There are other versions of the tag that also seem to have worked in my testing:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 4.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

We had ours set to the following, and it caused the error to come up:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">

That may have possibly come from a previous version of Visual Studio, and when users weren’t using IE9, everything was fine, but as soon as an IE9 user accessed our problem site, the error occurred.

As always… Let me know if this helped you or not.

Wait for jQuery ajax functions to complete

2013-06-14T11:30:00.000+02:00

This is something that kept me busy for a little while. There weren't many explanations that helped me to see how this works, but I managed to get something that worked for me.

I needed to return a json string from a handler and then check that it existed. My problem is that because jQuery is asynchronous, my validation code always fired before the string was returned from the .ajax function call had completed. This mean't that I couldn't check that my order contains the required currency data.

The key is to use $.when...then(function...

$.when will allow the code to complete the function calling the $ajax code, before continuing with the specified function.

This is how I got it working...

var CurrentOrderCurrencyRows_json;

function GetCurrencyRows() {

var OrderId = 25;

var ReturnValue = "";

$.when(ReturnCurrencyRows(OrderId)).then(function () {

ReturnValue = ValidateCurrencyRowsExist("There are no currency data rows!")

// Do what you want with ReturnValue

});

}

function ReturnCurrencyRows(OrderId) {

var BaseURL = "http://localhost/testapp/handlerFolder/";

var url = BaseURL + "ReturnOrderCurrencyRows_json.ashx?id=" + OrderId;

if (url != "") {

return $.ajax({

type: "GET",

url: url,

data: "",

dataType: "json",

success: function (data, status) {

CurrentOrderCurrencyRows_json = data;

error: function (data, status) {

alert('Error: ' + status);

}

});

}

function ValidateCurrencyRowsExist(ReturnErrorMessage) {

if (CurrentOrderCurrencyRows_json != undefined) {

return "";

}

else {

return ReturnErrorMessage;

}

Note: The above code will not work unless you call the $.ajax function specifying "return"

Good luck, and as always... Feedback is very very welcome.

jQuery ajax().load caches url

2013-04-19T13:06:00.000+02:00

In my mind, the jQuery ajax().load functionality is possibly one of the best things about jQuery.

I ran into a problem that drove me nuts for a little while...

I have a div:

I wanted to load some html into it each time I show a popup that contains it, like this:

// Page Variables

var ParsedURL;

var port;

var BaseUrl = "";

$(function () {

var url = document.URL;

ParsedURL = parseUri(url);

port = ParsedURL.port;

if (port != "") {

port = ":" + port;

}

ShowStatusesDDL();

ReadAndDisplayCookieData();

});

function ShowStatusesDDL() {

// Build the Base URL

BaseUrl = ParsedURL.protocol + "://" + ParsedURL.host + port + ParsedURL.directory;

// Add the rest of the text to the url for the BuildStatusDropDownList Handler

var LoadUrl = BaseUrl + "WebHandlers/BuildStatusDropDownList.ashx?t=" + ParsedURL.queryKey["t"] + "&id=" + ParsedURL.queryKey["id"];

$('#divStatus').load(LoadUrl);

}

The problem with this code, is that every time the .load method runs, the url is the same. The .load method caches the url, and if it isn't different each time the .load method runs, it will return the cached return values.

To fix this you need to make the url unique every time it runs, like this:

// Page Variables

var ParsedURL;

var port;

var BaseUrl = "";

$(function () {

var url = document.URL;

ParsedURL = parseUri(url);

port = ParsedURL.port;

if (port != "") {

port = ":" + port;

}

ShowStatusesDDL();

ReadAndDisplayCookieData();

});

function ShowStatusesDDL() {

// Build the Base URL

BaseUrl = ParsedURL.protocol + "://" + ParsedURL.host + port + ParsedURL.directory;

// Build a Globally Unique Identifier to add to the url to make it unique every time it is loaded -

// This is because jQuery.load caches the url and won't re-load it each time unless the url is different

var RandomGuid = guid();

// Add the rest of the text to the url for the BuildStatusDropDownList Handler

var LoadUrl = BaseUrl + "WebHandlers/BuildStatusDropDownList.ashx?t=" + ParsedURL.queryKey["t"] + "&id=" + ParsedURL.queryKey["id"] + "&guid=" + RandomGuid;

$('#divStatus').load(LoadUrl);

}

function S4() {

return (((1 + Math.random()) * 0x10000) | 0).toString(16).substring(1);

}

function guid() {

return (S4() + S4() + "-" + S4() + "-" + S4() + "-" + S4() + "-" + S4() + S4() + S4());

}

Pretty basic, but if you don't know about the .load method caching, it will confise the hell out of you.

How to learn to write software

2013-01-08T16:36:00.000+02:00

Learning how to write software is one of those things that you have to do in such a way that it suits you.

Some people enjoy an environment in which there is a structured approach, and they have someone who has some form of curriculum that is followed, teach them. They are given the history of software development, the theory behind software development and some syntax to work with. They are told how that syntax fits together with other syntax and the reasoning behind why it is like that. Then they are given tasks to do to demonstrate their understanding.

Others like to learn how to write software on their own. That’s how I did it, and I would like to think that I’m not bad at what I do.

I’m not going to say that one method of learning how to write software is better than any other method, simply because I only really know about the method I used. I don’t have any fancy degrees or anything like that. What I do have is the knowledge that I have been employed for a long time by many different companies to write software that did what they needed and wanted. I’m definitely not the world’s best programmer, but I’m also not the worst.

I learned to write software by having a need to do something on a computer, and at the time, not knowing how to make it happen. So, the first step for me was to decide to do it myself.

I could have called a programmer in to do the work, but that would have cost money I didn’t have. Besides, I love computers, so development was kind of a natural way to go for me to go.

I didn’t start out programming totally green. I played with a Sinclair ZX Spectrum computer as a kid. It was the latest and greatest computer that I could get my hands on at the time. It plugged into a TV, didn’t have any way to store the programs that were typed in, unless you plugged a tape recorder into it to store it on cassette tape. It did have 16k of ram and could display 16 colours on the TV it was plugged into.

I started out buying books with the code that once typed into the computer and executed, would provide me with hours of gaming pleasure, but it used to take hours to enter the code into the computer before I could play the game. I saved the games onto cassette tape, and if I was lucky enough to have the saved game work the next time I tried to load it, I was able to play them again and again.

That’s was my first introduction to coding. The language was Basic. I didn’t really learn to programme through this experience, but I did get to understand how the code fitted together and that was a decent base to start on.

Many years later, I had the opportunity to work in a software development company as their technical manager, and since I had a basic understanding of how software was put together, I began to learn. We were using VB3 and VB4 at the time, and those were light years ahead of the old Spectrum Basic I first encountered, but I seemed to pick it up pretty easily.

I never actually wrote much code for that company, but I did do some. I still didn’t really know what I was doing as a developer until I left that company and began looking after my own client’s hardware and software needs. I had a client that needed a very custom application written. I quoted them, and when they accepted my quote, I had to find out how to actually write an application that did what they wanted, or find someone who would charge me to write it for me. I chose to write it because I couldn’t afford to pay someone else to do it for me.

Their requirement was pretty simple:

They needed to record the volume of liquid cosmetics that were filled into their containers for quality control needs. They wanted to record the volume by weight, therefore needed to be able to enter the specific gravity of the liquid going into the containers. Fortunately they provided me with the formula to work that out. Scales were connected to the computer and values came in from them, through serial cables, that the application had to record in a database, linking a product, batch and the values to each other.

There were some rules:

Must be password protected.
Must have a scale calibration module.
Must store products for linking to container sizes and batch numbers.
Must have various reports for auditing purposes.

I really didn’t know enough about coding at the beginning of the project to get it done. I had been paid and spent a deposit so had no choice but to deliver an application.

That’s where my learning how to write software really began.

I knew come basic syntax and how to use it, but didn’t really know how to write software, so I just started at the beginning. I knew that I had to provide access to a database for storage and decided to use SQL Server. I was writing in VB6, so found out how to use ADO to connect to SQL Server.

The first thing I did was design the user table and wrote the user login module. Once I had that done, I knew how to access, insert records, update records and delete in a SQL database. From there it was just a case of deciding what to do next and do it. If I didn’t know how to do what I wanted to do, I found out.

That’s how I learned how to write software. It probably wasn’t the best way to go about it, but it worked for me.

My advice to anyone wanting to learn how to write software, who doesn’t want to go the formal route, is to get hold of a computer that can run Visual Studio Express and to decide on a project, then to find out how to write code. Hopefully you have some knowledge about computers, but the most important thing Is to actually dive in and get dirty.

If you are thinking about learning to write software, you aren’t learning, you are thinking about learning.

Don’t think. Do!

How did you learn?

Copy or clone a DataTable and insert rows

2013-01-07T08:59:00.004+02:00

From time to time you may have the need to make an exact duplicate of a DataTable. This is very easily done using the .clone() method.

The obvious place to start is to create a DataTable to use as the source...

' Create the Datatable

Dim dtSource As New DataTable("Contacts")

' Create some columns for the table

Dim colID As New DataColumn("id", Type.GetType("System.Int32"))

Dim colFirstName As New DataColumn("FirstName", Type.GetType("System.String"))

Dim colLastName As New DataColumn("LastName", Type.GetType("System.String"))

' Add the columns to the Datatable

dtSource.Columns.Add(colID)

dtSource.Columns.Add(colFirstName)

dtSource.Columns.Add(colLastName)

' Create some rows to the DatatTable

Dim row1 As DataRow = dtSource.NewRow()

row1("id") = 1

row1("FirstName") = "John"

row1("LastName") = "Smith"

Dim row2 As DataRow = dtSource.NewRow()

row2("id") = 2

row2("FirstName") = "James"

row2("LastName") = "Bond"

Dim row3 As DataRow = dtSource.NewRow()

row3("id") = 3

row3("FirstName") = "Jane"

row3("LastName") = "Doe"

' Add the rows to the Data Table

dtSource.Rows.Add(row1)

dtSource.Rows.Add(row2)

dtSource.Rows.Add(row3)

Now we have a DataTable with 3 columns and 3 rows called Contacts.

To make a copy of it we use the .Clone() Method...

Dim dtTarget As DataTable = dtSource.Clone()

That's all there is to making an exact copy of the DataTable. One very important thing keep in mind is that the .Clone() method will only copy the structure and NOT the data or rows from the source DataTable.

If you want to import the rows from the source to the target DataTable, you must use the .ImportRow() method.

For Each row As DataRow In dtSource.Rows

dtTarget.ImportRow(row)

As always... Comments are welcome.

Pass Greater Than or Lesser Than in XML

2012-12-10T10:43:00.002+02:00

If you have a need to pass a greater than (>) or lesser than (<) symbol to a SQL stored procedure using a XML string, then this may help you...

Most of the stored procs that I work with in my work environment require me to pass data in to them using XML. This is not by personal choice but it is required to keep to standards set a loooong time ago.

The stored proc builds a query based on the WhereClause that is passed within the XML string.

Passing a where clause that contains the greater than (>) or lesser than (<) symbols will cause an error in your query because they are reserved as building blocks of an XML string. I get around this by using substitution characters like this...

Dim StartDate As String = "2012-12-01"

Dim EndDate As String = "2012-12-07"

Dim XML As New StringBuilder("Exec sp_ReturnData '<Contact Debug=""1"">")

XML.Append("<Record WhereClause="" Where ActionDate [gt]= '" & StartDate & "' And ActionDate [lt]= '" & EndDate & "'"" />")

XML.Append("</Contact>'")

In my stored proc there is a variable declared as @WhereClause which contanes the "WhereClause" that I pass in through the XML.

I perform a character substitution on @WhereClause like this...

Set
@WhereClause = Replace(@WhereClause,'[lt]','<')

Set
@WhereClause = Replace(@WhereClause,'[gt]','>')

And then I set the sql command and add @WhereClause to it...

Set @SQL = 'SELECT FirstName, Surname From MyTable '

Set @SQL = @SQL + @WhereClause

You can pick your own characters to substitute. Just make sure they aren't characters that you might use elsewhere, or the wrong characters will be substituted.

Do you use a different method to do this? Let me know in the comments.

Building a development machine - Start to finish...

2012-11-19T11:42:00.000+02:00

I was recently forced to re-load all of the required software on a new development machine.

No! I'm not stupid. I may be a little crazy, but that's debatable.

I was forced to load the machine because some wonderful people (read thieves) decided that my development laptop and all other computer equipment in my home, should be theirs.

It took 4 days for my office to buy me a new machine, and in those 4 days, I went a little nuts from boredom. No form of computer for more than a day, and I feel it big time.

Anyway... The new laptop arrived with Windows 7 installed.

The first step was to install Visual Studio 2010. That took what seemed to be a lifetime. Then I installed SP1, and that strangely enough took even longer to install.

SQL Server was next. 2008 R2 takes another life time to install and configure. I then had to copy the live DB to my laptop. It's a whole 28Gig!!! That took about 5 or 6 hours to copy, because low and behold, there happened to be network connectivity issues in the office on that particular day.

So now I had a machine that I could at least begin to work on.

Then I found out just how many other little, but essential pieces of software that I use on a daily basis to do seemingly simple things with...

Paint.Net for those little image creation and re-sizing, colour sampling and general editing of images.
Notepad2 or Notepad++ for simple or complex text editing.
Google Chrome and/or Firefox for consistency checking of web apps.
Any nice snipping tool for grabbing of sections of the screen.
Dropbox or Google Drive for cloud storage of almost anything you want to backup.
Acrobat Reader for opening PDF docs.

There are also those million and one little apps that I have written over the years that make my development life simpler.

All in all, I think it took me about 30 hours to get to a point where I could actually do some work. This also excludes re-writing those little apps, that I forgot to backup, that perform small but crucial tasks for me. I know my very big, huge (some very bad swear word here), mess up!

How about you... How long does it take you to get a new machine going to a point of being able to get some work done?

IIf in c#

2012-09-25T13:27:00.001+02:00

Visual Basic and c# are very similar. That's my opinion, but in some small cases there is no similarity.

The VB IIf function is one example of which there is nothing that looks even slightly similar in c#.
The equivalent in c# is…

a == "1" ? true : false;

How to use this is pretty simple…
    bool ReturnedValue = a == "1" ? true : false;
or
    int ReturnedValue = a == "1" ? 5 : 10;
or
    string ReturnedValue = a == "canine" ? "dog" : "cat";

However you decide to use it, it looks a bit strange to a veteran VB user.
To make it more VB friendly I have these methods that look and function like the VB IIf function…

    private object IIf(bool Expression, object TruePart, object FalsePart)
    {
      object ReturnValue = Expression == true ? TruePart : FalsePart;

      return ReturnValue;
    }

    private string IIf(bool Expression, string TruePart, string FalsePart)
    {
      string ReturnValue = Expression == true ? TruePart : FalsePart;

      return ReturnValue;
    }

    private bool IIf(bool Expression, bool TruePart, bool FalsePart)
    {
      bool ReturnValue = Expression == true ? TruePart : FalsePart;

      return ReturnValue;
    }

    private int IIf(bool Expression, int TruePart, int FalsePart)
    {
      int ReturnValue = Expression == true ? TruePart : FalsePart;

      return ReturnValue;
    }

Use them like this…
string ReturnedValue = IIf(aa == "canine", "dog", "cat");

Happy coding

Create a DataTable easily

2012-08-23T09:48:00.001+02:00

I have a need to create Data Tables for many reasons in my quest for complete projects. If you need to do it, and you, like me, find the whole thing of defining each column and type a big schlep, check this out.

Public Shared Function BuildDataTable(ByVal TableName As String,

ByVal Parameters As List(Of TableParams)) As DataTable

Dim dtReturn As New DataTable(TableName)

Try

For Each param As TableParams In Parameters

dtReturn.Columns.Add(New DataColumn(param.ColumnName, param.ColumnType))

Catch ex As Exception : Throw

Finally

End Try

Return dtReturn

End Function

Public Class TableParams

Public ColumnName As String

Public ColumnType As Type

Public Sub New(ByVal ColumnName As String, ByVal ColumnType As Type)

Me.ColumnName = ColumnName

Me.ColumnType = ColumnType

End Sub

End Class

Use the above Function like this…

Dim TableParams As New List(Of TableParams)

TableParams.Add(New TableParams("id", Type.GetType("System.Int32")))

TableParams.Add(New TableParams("CompanyName", Type.GetType("System.String")))

TableParams.Add(New TableParams("EMail", Type.GetType("System.String")))

TableParams.Add(New TableParams("FirstName", Type.GetType("System.String")))

TableParams.Add(New TableParams("Surname", Type.GetType("System.String")))

Dim dtInviteList As DataTable = Common.BuildDataTable("ContactDetails", TableParams)

Word cannot register your account

2012-08-23T09:29:00.001+02:00

I know that this isn't .net related, but I couldn't find much to help with this problem anywhere, and since I managed to solve it for myself, I thought I would post my solution here. I hope you don't mind.

If you receive the message "Word cannot register your account" when trying to register your account on Blogger.com, try the following…

I recently found something that may help with this problem. It is caused by your google account not allowing access to "less secure" applications. MS Word is one of them, and access is denied by default.

To allow less secure applications to sign in using your Google account, you need to change the access setting.

Follow the following link and select "Turn On":

https://www.google.com/settings/security/lesssecureapps

This will allow you to log into blogger through MS Office, and to post to your blog.

Please let me know how it works out for you in the comments.

~~1. Log into the Blogger settings page for your account.~~
~~2. Send an "Author" invite to yourself at a different Google account to the one you used to log into Blogger with.~~
~~3. Follow the link sent to your 2nd Google account, and log into Blogger using the 2nd Google account. This will set your 2nd account up on your blog with "Author" privileges.~~
~~4. Go back to word and use your 2nd Google account credentials to register using word on Blogger.~~
~~This worked for me. I hope it does for everyone else with this problem.~~
~~I haven't tried it, but it may just work to see if you can change your main Google account to have author privileges in Blogger instead of or as well as having "Admin" privileges.~~

InputBox for c#

2010-08-23T11:08:00.001+02:00

One of the little things that has been left out of the c# tool box is the vb style input box that allows you to input a string into a text box and have the string returned back to you.

This is my solution...

Create a little FixedToolWindow that looks like this...

It needs a label, a text box and two buttons.

Name your form and controls:

Form - InputBox.
Caption Label - lblCaption.
Text Box - txtInputText.
Ok Button - btnOk.
Cancel Button - btnCancel.

lblCaption is used to display any instructions you have for the user, txtInputText for the text to input, btnOk to cause dialogResult.OK to be returned to the calling code and btnCancel to cause DialogResult.Cancel to be returned to the calling code.

Set the form's AcceptButton and CancelButton properties to btnOk and btnCancel respectively.

You must go to the designer code for the form itself and set the caption label and input text box to public so they will be accessible when you use the form.

     public System.Windows.Forms.Label lblCaption;  
     public System.Windows.Forms.TextBox txtInputText;

Set the DialogResult of btnOk button to "OK", and the DialogResult of btnCancel button to "Cancel"

Then use the following code on the form to receive a caption and title to display and default value for the input string...

   public partial class InputBox : Form  
   {  
     /// <summary>  
     /// Caption for the Input Box  
     /// </summary>  
     private string Caption;  
     /// <summary>  
     /// Title for the Input Box  
     /// </summary>  
     private string Title;  
     /// <summary>  
     /// Default text for the Imput Box  
     /// </summary>  
     private string DefaultText;  
     /// <summary>  
     /// Provides a string based input function to get feedback from the user  
     /// </summary>  
     /// <param name="_Caption"></param>  
     /// <param name="_Title"></param>  
     /// <param name="_DefaultText"></param>  
     public InputBox(string _Caption, string _Title, string _DefaultText)  
     {  
       InitializeComponent();  
       Caption = _Caption;  
       Title = _Title;  
       DefaultText = _DefaultText;  
     }  
     private void InputBox_Load(object sender, EventArgs e)  
     {  
       this.Text = Title;  
       lblCaption.Text = Caption;  
       txtInputText.Text = DefaultText;  
     }  
   }

You will use it like this...

         InputBox inputbox = new InputBox(Caption, Title, DefaultText);  
         DialogResult dlg = inputbox.ShowDialog();  
         if (dlg == DialogResult.OK)  
         {  
           string firstName = inputbox.txtInputText.Text;
         }

As you can see it is then pretty simple to use, and has pretty much the same functionality as the vb Input Box control.

The c# and VB.net wars...

2010-08-05T11:32:00.000+02:00

Why is it that whenever there is a difference in opinion, people tend to get violent and nasty about it?

Once upon a time there was Borland GW Basic. That was about 20 or so years ago.

Do you remember having to number your lines of code? I do, and if that makes me old, then so be it.

After a little while there was Q Basic from Microsoft. To get any sort of graphical anything, you had to use funny things like any normal keyboard character.

Microsoft then brought VB version 1 out. While it still was run and compiled in a DOS environment, it actually has a visual element to it that allowed the developer to create a GUI for their apps.

When windows 3.0 came out, Microsoft came up with VB3. I'm not really sure where VB2 went, but they provided developers with the ability to create apps with niceer looking GUI's. It wasn't great, but it worked.

By this time Borland seemed to have given up on Basic as a language, and came up with C and Delphi.

C and C++ became known as the elite developer's language, and Delphi, while being taught in schools, never really made it to the big time.

As the versions of Windows became bigger and more extensive, so did the VB versions.

Microsoft went on to VB4, VB5 (very briefly) and then on to VB6. Each version was a little "better" and offered more extensive featured.

VB6 stuck around for many years, with most C and C++ developers laughing at the VB6 developers because VB didn't have the complexities that C and C++ had. There was even some guy that asked me what language one of my applications was written in, and when I said VB6, he laughed and said it looked like it. How stupid is that. Can you not write an application in C++ that someone else may not like the look of?

If anything VB6 gave a lot of developers what they wanted and needed. Something to create applications quickly and easily with. This is why C and C++ developers laughed at the VB6 crowd. They were, and are still of the opinion that if you cannot control the memory allocations yourself, then you are a moron, and need to learn how to write real applications.

VB6 had one huge hole in its armor. DLL Hell. I can't tell you how often I was brought to a shaking rage at having to deal with the problems brought about my this. I even once managed crashed the OS of one of the CEO's of one of the biggest companies in South Africa, to the point of the OS needing to be re-installed from scratch because one of our dll's over wrote a newer one. You get my point, I'm sure.

After the many years that VB6 stuck around, Microsoft came up with their holy grail of ideas on the software development front. They, in theory had come up with a way to get rid of dll hell, and then dot net framework was born.

VB.net came out as part of the Visual Studio .net suite of development tools. This included a new visual version of C++. Version 1.0 of the framework was cool, but was quickly replaced with version 1.1.

It tool me a long time to get the hang of VB.net. ADO.net threw me. Call it what you like, but there are far more differences between VB6 and VB.net than there are similarities. Despite the differences, it was kept in the VB suite, probably because if the syntax similarities.

I do wonder if anyone at Microsoft ever thought about scrapping the VB line, and just moving over to c#. It would have been just as much effort for me to learn c# way back when, instead of VB.net. If anyone can tell me why VB was kept, please do.

It wasn't really until version 2.5 of the framework came out that the "c# is better" thing started.

I currently use both c# and VB.net. I find c# to be a little easier and quicker to develop in. Both can do pretty much exactly the same things, so why keep both?

I do feel that VB.net will be fazed out over the years, but I doubt it will be any time soon.

I only started working with c# in late 2007, and was pretty happy with my ability to work with it after only a week or two of using it.

My current job is at a company that claims to be a VB.net only shop, but there are PHP, c# and VB.net apps here.

While I do prefer to work in c#, I find that VB.net gets the job done just as well.

So why this hate for VB.net by c# developers? as far as I know VB.net developers don't hate c#.

Some say that they dislike the way functions and subs are started and ended. Others just don't like the syntax because it is too cluttered or whatever.

I personally don't care either way. The way I look at it, is that I am a professional, and I am paid to write software. If my employer wants me to use VB.net, then that is what I will do.

Apparently c# developers get paid about 30% more than VB.net developers. Really? I'm being paid the same as any c# developer, and I get the job done for my employer.

What's the problem?

(417) Expectation Failed - Twitter and .net aren't nice to each other

2010-07-22T13:31:00.001+02:00

I have been writing applications that work with the Twitter API for a few years now. It's pretty simple, but if you don't know where to start, you could run into some trouble.

The first big problem I ran into was the "(417) Expectation Failed" error that Twitter started to return one day out of the blue.

I was using the Yedda dll to do all of my interaction with the Twitter API, and I didn't really know how it worked, so I went through it for a while, getting to know it.

I then got a little frustrated with it, and wrote my own Twitter class to use. I still had the "(417) Expectation Failed" error coming back when I tried to post to the API.

After a little research, I found out that the API no longer likes the HTTP header with the "100-Continue" value.

To fix this, I needed to add the following line of code to my method:

"request.ServicePoint.Expect100Continue = false;"

This fixed my Post code, and I was happy for a little while.

Then my world came crashing down, and the error came back. Again, it was without warning, and I was left scratching my head.

I went back to Google, and after a few hours searching, I found the solution.

This is how I did it:

     public static String ExecutePostCommand(String url, String UserName, String Password, String data)  
     {  
       HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);   
       request.ServicePoint.Expect100Continue = false;  
       try  
       {  
         if (!String.IsNullOrEmpty(UserName) && !String.IsNullOrEmpty(Password))  
         {  
           request.Credentials = new NetworkCredential(UserName, Password);  
           request.ContentType = "application/x-www-form-urlencoded";  
           request.Method = "POST";  
           byte[] bytes = Encoding.UTF8.GetBytes(data);  
           request.ContentLength = bytes.Length;  
           using (Stream requestStream = request.GetRequestStream())  
           {  
             requestStream.Write(bytes, 0, bytes.Length);  
             //HttpWebResponse response = (HttpWebResponse)request.GetResponse()  
             using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())  
             {  
               using (StreamReader reader = new StreamReader(response.GetResponseStream()))  
               {  
                 return reader.ReadToEnd();  
               }  
             }  
           }  
         }  
       }  
       catch (WebException ex)  
       {  
         if (ex.Response is HttpWebResponse)  
         {  
           if ((ex.Response as HttpWebResponse).StatusCode == HttpStatusCode.NotFound)  
           {  
             return null;  
           }  
         }  
         throw ex;  
       }  
       return null;  
     }

You will see that I am using a HTTPWebRequest in the code. The original Yedda dll used a WebRequest instead.

My code works now, and I'm happy, that's until the next little/big API change that makes me pull my already thinning hair out.

Get mouse location on form no matter what

2010-06-10T10:31:00.003+02:00

Someone asked me how to get the mouse location on a windows form no matter what controls are on the form.

A lot of suggestions were made about using the following...

Place a label on the form and use the following code in the Mouse Move event on the form.

   Private Sub Form1_MouseMove(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseMove
   Label1.Text = Cursor.Position.ToString()
 End Sub

While the code in the Mouse Move event handler will work, there will be a problem in that it will stop working as soon as the mouse moves over a control on the form. This is because the Mouse Move event of the control takes over. Your code is only in the Mouse Move even handler of the form.
To handle this you could create a Mouse Move even handler for every control on your form, and work out the position of the mouse on the form with some clever code.

I have to ask... What happens if you have many container controls all full of other controls. Do you really want to have to create a Mouse Move event handler for each one, and then have to work out if the control your cursor is moving over is within a container control?

My guess is no!

I have a much simpler solution...

Add a timer to your form, set the interval property to something like 10 milliseconds, and use the following in a Timer Tick event handler...

   Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick 
    Label1.Text = Me.PointToClient(Me.MousePosition).ToString() 
  End Sub

This will give you the position of the mouse cursor on the form, no matter what controls your cursor moves over.

Transparent Windows Forms Label Control

2010-06-08T10:21:00.019+02:00

I was recently asked how to make a windows forms Label control background transparent.

Being mostly a web app developer, I simply answered that it was easy and all you have to do is set the back color of the label to color.Transparent.

I tried it, and to my shock and horror, I was wrong. It is not that simple, because that is not the way that .net windows applications render the background of controls.

The way it works, is that the control (label in my case) will take on the back color of its parent control when you set its back color to Transparent. This is usually the form's back color, causing any controls under the label will have a nice fat rectangular shape, the same color of its containing control around the contents of the label.

Some people suggest that you can set the form's Transparency Key property to the same color as the back color of the label. All that does is make the form transparent so you can see whatever is behind the form through it, where that color is rendered on the form.

The best solution I came across is to create a new label control in your project...

http://www.doogal.co.uk/transparent.php

According the the author, there can be a problem in rendering the label in some cases, but it worked out perfectly for me.

The code is great, but is missing the how to use it part for those of you who don't know how to implement it.

To use it...

Basically you must create a new class in your application and copy the following code into your class (replace everything created for you with the code):

[c#]

 using System;
using System.Drawing;
using System.Windows.Forms;
namespace WinFormsControls
{
 public class TransparentLabel : Control
 {

   public TransparentLabel()
   {
     TabStop = false;
   }

   protected override CreateParams CreateParams
   {
     get
     {
       CreateParams cp = base.CreateParams;
       cp.ExStyle |= 0x20;
       return cp;
     }
   }
 
   protected override void OnPaintBackground(PaintEventArgs e)
   {
     // do nothing
   }
 
   protected override void OnPaint(PaintEventArgs e)
   {
     using (SolidBrush brush = new SolidBrush(ForeColor))
     {
       e.Graphics.DrawString(Text, Font, brush, -1, 0);
     }
   }
 }
}

[VB]

 Imports System 
Imports System.Drawing 
Imports System.Windows.Forms 
Namespace WinFormsControls 
  Public Class TransparentLabel : Inherits Control 
    Public Sub TransparentLabel() 
      TabStop = False 
    End Sub 
    Protected Overrides ReadOnly Property CreateParams() As CreateParams 
      Get 
        Dim cp As CreateParams = MyBase.CreateParams 
        cp.ExStyle = cp.ExStyle Or &H20 
        Return cp 
      End Get 
    End Property 
    Protected Overrides Sub OnPaintBackground(ByVal e As PaintEventArgs) 
      ' do nothing 
    End Sub 
    Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs) 
      Using brush As New SolidBrush(ForeColor) 
        e.Graphics.DrawString(Text, Font, brush, -1, 0) 
      End Using 
    End Sub 
  End Class 
End Namespace

Use the control like this:

[c#]

TransparentLabel lblTrans = new TransparentLabel();
lblTrans.Height = 35;
lblTrans.Width = 35;
lblTrans.Top = 50;
lblTrans.Left = 50;
lblTrans.Text = "l";
lblTrans.Font = new Font("Wingdings", 30);
this.Controls.Add(lblTrans);
lblTrans.Visible = true;
lblTrans.BringToFront();

[VB]

Dim lblTrans As New TransparentLabel()
lblTrans.Height = 35
lblTrans.Width = 35
lblTrans.Top = 50
lblTrans.Left = 50
lblTrans.Text = "l"
lblTrans.Font = New Font("Wingdings", 30)
Me.Controls.Add(lblTrans)
lblTrans.Visible = True
lblTrans.BringToFront()

Remember to include the following at the top of your code window to be able to use the control on your form:

[c#]

 using WinFormsControls;

[VB]

 Imports YourProjectName.WinFormsControls

If you want to use the control in multiple projects, I would suggest that you add this code to a dll and include the dll in your project.

Happy coding.

Shifting Perspective

2010-03-10T09:16:00.001+02:00

Software development is an ever changing environment. Projects come and projects go, but one thing that will stay in place, hacking away at the hot keyboard is the poor developer.

This creature is destined to have blurry vision, carpel tunnel syndrome, and a very high caffeine to blood ratio. This mere mortal is expected to do the impossible in the shortest possible time, without thought to feelings or exhaustion levels.

Does this wonder of modern society care? No! He thrives on the unknown challenges that are thrown in his direction.

There is one thing that will always make me cringe.

The software development manager.

Nine times out of ten, the software manager comes from a development background himself. He spent hour after hour slapping away at his keyboard, churning out line after line of code, only to have a bug report longer than his arm thrown in his face the day after submitting his code.
Does he remember the pain, the anguish? Again, No!

The software development manager, will have challenges of his own. Delivering on time is his primary focus, and if he has a new task that needs to be done “now”, then he will seldom think about the state of the poor developer’s mind while he is churning his code out.

He will arrive at the side of the developer seemingly out of this air, and demand a shift of focus. This requires the poor long suffering developer, to perform super human feats of the mind in order to focus on this new task that is going to interrupt his thought process.

Some of the tasks that will have to be performed are:

1. Re-route his brains neural pathways to be able to focus on his manager’s face instead of his screen and keyboard.

2. Actually physically have to restrain him self from ripping the said manager’s face off for interrupting him.

3. Listen and reply when needed to any thing the manager requests.

4. Ask questions about the new task.

These go on and on, but the bottom line is that he basically, now has to start thinking about something else that is supposedly more important than his interrupted task. This requires a lot of locating his thinking part of his brain, which was shut down in the process of listening to his manager.
Once he locates it, he can then start to think about what is needed to start his new task.
He has to be able to visualize what is needed, so that he can even begin to write any code. The code itself isn’t all that difficult once you get to know it.

It is the calculations, flows, designs of the GUI, the duplicative code that needs to be centralized, etc.

There a million and one small little seemingly (on their own) stupid bits of code that together for an application that does wonderful things.

Interrupt a developer at work at your own peril and cost!

Simplifying the ExecuteNonQuery Method

2009-06-23T06:36:00.002+02:00

Tagging onto the last post, I have another two functions that make my life easier...

You still need to pick up a connection string from your Web.Config for both of these functions:

Public static string GetConnectionString()

{

return System.Configuration.ConfigurationManager.AppSettings["sqlConnectionString"];

}

Simplifying the ExecuteNonQuery Method:

public static String ExecuteNonQuery(String lvCommand)

{

// This will execute a SQL Command (Update or Insert Into) and will return the number of records String lvReturn = "0";

// Setup your connection to your database

SqlConnection cn = new SqlConnection(GetConnectionString());

// Create a SQLCommand object

SqlCommand lvSQL = new SqlCommand(lvCommand, cn);

try

{

// Open a connection to your database

cn.Open();

// Execute your query

lvReturn = lvSQL.ExecuteNonQuery().ToString();

}

catch (Exception ex)

{

// If there is an error set lvReturn to "0"

lvReturn = "0";

}

finally

{

// Whatever happens, check to see if the connection is still open and if it is, close it

if (cn.State != ConnectionState.Closed)

{

cn.Close();

}

// Return the number of records affected

return lvReturn;

}

To use the function, call it like this...

String lvCommand = "Update A_Table Set A_Field = 'The String' Where AnotherField = 'Another String'";

Int32 lvAffectedRowCount = Int32.Parse(ExecuteScalar(lvCommand));

Again, Pretty simple.

Database Actions that Drive Me Nuts

2009-06-18T08:06:00.002+02:00

There are so many actions while writing software that you have to do over and over and over... again.

Things like opening database connections, filling a dataset or data table with data from the database, executing a SQL command and retrieving a scalar value from a database. 99% of the time I write database driven apps, and I have to do these things all the time. They are so boring and repetitive!!!

These small functions help me make these action tolerable, and quite simple to do:

There is a small function that these functions call, called GetConnectionString. This basically gets the connection string that you set in your Web.Config file.

public static string GetConnectionString()

{

return System.Configuration.ConfigurationManager.AppSettings["sqlConnectionString"];

}

Simplifying the ExecuteScalar Method...

public static String ExecuteScalar(String lvCommand)

{

// If a record is found, this will return the first column of the first row of the found data

String lvReturn = "";

// Setup your connection to your database

SqlConnection cn = new SqlConnection(GetConnectionString());

// Create a SQLCommand object

SqlCommand lvSQL = new SqlCommand(lvCommand, cn);

try

{

// Open a connection to your database

cn.Open();

// Execute your query

lvReturn = lvSQL.ExecuteScalar().ToString();

}

catch (Exception ex)

{

// If there is an error set lvReturn to ""

lvReturn = "";

}

finally

{

// Whatever happens, check to see if the connection is still open and if it is, close it

if (cn.State != ConnectionState.Closed)

{

cn.Close();

}

// Return the data that was found or the empty string is none

return lvReturn;

}

To use this function call it like this...

String lvCommand = "Select AdminStatus From YourTable Where UserName = 'SomeName'";

String lvAdminStatus = ExecuteScalar(lvCommand);

It’s that simple. No having to create your connection, create your sqlcommand object, open your connection, execute your command and close your connection every time you want to use the ExecuteScalar method.

How to - Send a SMTP E-Mail in ASP.Net

2009-01-06T14:01:00.012+02:00

One of the things that a lot of web developers need and want to do, is to send E-Mails from their pages in response to various actions.

It is pretty easy to do, and I have put a small web page example together to show you how to do it.

[Web Page HTML]

<table style="font-family: Tahoma; font-size: 8pt">
<tr>
<td style="text-align:center">
<a href="Default.aspx">Home</a>
</td>
</tr>
</table>
<table style="font-family: Tahoma; font-size: 8pt; width: 550px">
<tr>
<td style="width: 550px; text-align: center">
<asp:Label ID="Label1" runat="server" Text="Send E-Mail" style="font-family: Tahoma; font-size: 16pt"></asp:Label>
</td>
</tr>
</table>
<table style="font-family: Tahoma; font-size: 8pt; width: 550px">
<tr>
<td style="width: 100px">
<asp:Label ID="lblTo" runat="server" Text="To"></asp:Label>
</td>
<td style="width: 400px">
<asp:TextBox ID="txtTo" runat="server"></asp:TextBox>
</td>
<td>
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" ControlToValidate="txtTo" runat="server" ErrorMessage="Required"></asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td style="width: 100px">
<asp:Label ID="lblSubject" runat="server" Text="Subject"></asp:Label>
</td>
<td style="width: 400px">
<asp:TextBox ID="txtSubject" runat="server"></asp:TextBox>
</td>
<td>
<asp:RequiredFieldValidator ID="RequiredFieldValidator2" ControlToValidate="txtSubject" runat="server" ErrorMessage="Required"></asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td style="width: 100px">
<asp:Label ID="lblMessage" runat="server" Text="Message"></asp:Label>
</td>
<td style="width: 400px">
<asp:TextBox ID="txtMessage" runat="server" TextMode="MultiLine" Rows="10" style="width: 100%"></asp:TextBox>
</td>
<td>
<asp:RequiredFieldValidator ID="RequiredFieldValidator3" ControlToValidate="txtMessage" runat="server" ErrorMessage="Required"></asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td style="width: 100%" colspan="2">
<asp:Button ID="btnSend" runat="server" Text="Send E-Mail" OnClick="btnSend_Click" />
<asp:Label ID="lblStatus" runat="server" Text=""></asp:Label>
</td>
</tr>
</table>

This will give you a page with a text box to enter the E-Mail address of the recipient, a subject and a message to be sent.

Copy and paste it between your page's opening and closing "form" element.

Next you will need to use the following code behind examples to make the page send the E-Mails...

[VB Code Behind Example]

Protected Sub btnSend_Click(ByVal sender As Object, ByVal e As System.EventArgs)
Dim lvFromAddress As String = "Senders_E-MailAddress"
Dim lvToAddress As String = txtTo.Text
Dim lvSubject As String = txtSubject.Text
Dim lvMessage As String = txtMessage.Text

lblStatus.Text = SendMail(lvFromAddress, lvToAddress, lvSubject, lvMessage)
End Sub

Private Function SendMail(ByVal FromAddress As String, ByVal ToAddress As String, ByVal Subject As String, ByVal Message As String) As String
Dim lvReturn As String = ""
Try
'create the mail message
Dim mail As New MailMessage()
Dim MailServer As String = "localhost"

'set the addresses
mail.From = New MailAddress(FromAddress)
mail.To.Add(ToAddress)

'set the content
mail.Subject = Subject
mail.Body = Message
mail.IsBodyHtml = True

Dim lvMailSender As New SmtpClient(MailServer)
lvMailSender.Send(mail)
lvReturn = "Message sent"
Catch
'lvError = Err.Number
lvReturn = "Error " & Err.Number & " - " & Err.Description
End Try

Return lvReturn
End Function

[C# Code Behind Example]

protected void btnSend_Click(object sender, EventArgs e)
{
String lvFromAddress = "Senders_E-MailAddress";
String lvToAddress = txtTo.Text;
String lvSubject = txtSubject.Text;
String lvMessage = txtMessage.Text;

lblStatus.Text = SendMail(lvFromAddress, lvToAddress, lvSubject, lvMessage);
}

protected String SendMail(String FromAddress, String ToAddress, String Subject, String Message)
{
String lvReturn = "";
try
{
//create the mail message
MailMessage mail=new MailMessage();
String MailServer = "localhost";

//set the addresses
mail.From = new MailAddress(FromAddress);
mail.To.Add(ToAddress);

//set the content
mail.Subject = Subject;
mail.Body = Message;
mail.IsBodyHtml = true;

SmtpClient lvMailSender;
lvMailSender = new SmtpClient(MailServer);
lvMailSender.Send(mail);
lvReturn = "Message sent";
return lvReturn;
}
catch(Exception ex)
{
lvReturn = "Error - " + ex.Message;
return lvReturn;
}
}

Its pretty simple to use.
Please let me know if you have any problems with the code.