.NET Notes

Formatting with String.Format and ToString

2012-03-31T10:13:00.001-04:00

        static void Main()
        {
            //
            // Format a ratio as a percentage string.
            // ... You must specify the percentage symbol in the format string.
            // ... It will multiply the value by 100 for you.
            //
            double ratio = 0.73;
            string result = string.Format("string = {0:0.0%}",
                ratio);
            Console.WriteLine(result);

            int value = 123;
            string a = string.Format("{0:0000}", value); // Too complex
            string b = value.ToString("0000"); // Simpler
            Console.WriteLine(a);
            Console.WriteLine(b);

            // Format as currency
            double expense = 1234.56;
            string str = expense.ToString("C");
            Console.WriteLine("Expense: {0}", str);

            // Format with parentheses
            str = String.Format("{0:(#####0.000)}", expense);
            Console.WriteLine("Expense: {0}", str);
        }

Output:
string = 73.0%
0123
0123
Expense: $1,234.56
Expense: (1234.560)

Standard Numeric Format Strings

F# Code: Hindley Milner Type Inference Sample Implementatio...

2011-06-23T17:24:00.000-04:00

F# Code: Hindley Milner Type Inference Sample Implementatio...: "// Learn more about F# at http://fsharp.net // Hindley Milner Type Inference Sample Implementation // ************************************..."

.NET 4.0

2011-04-08T23:39:00.000-04:00

http://msdn.microsoft.com/en-us/vcsharp/bb798022.aspx?wt.slv=TopSectionSee

.NET Framework 4.0

Introduction to Membership
Configuring an ASP.NET Application to Use Membership
Walkthrough: Managing Web Site Users with Roles
Creating and Configuring the Application Services Database for SQL Server
Roles and Views in the Application Services Database for SQL Server

SQL Server Reporting Services

2011-01-25T17:24:00.001-05:00

In this post, I will be talking about SQL Server Reporting Services (SSRS) 2008. Before I start discussing SSRS, I should mention that most of my reports development experience was with Crystal Reports, so I will compare SSRS features to those of Crystal Reports from time to time.

Overview & Features
SSRS Toolbox provides the following controls: Textbox, Line, Table, Matrix, Rectangle, List, Image, Subreport, Chart, Gauge. The most frequently used controls are the Textbox and Table.

Textbox -- can be used as both, a textbox and a label (if you make it readonly).
Table -- used for displaying data in a tabular format. It has Header Row and Detail Row, which is nice, because I can use just a Table in SSRS where I would have to use a subreport in Crystal Reports.

SSRS provides a powerful expressions engine based on Visual Basic syntax, a capabilty to add some vb.net code, and it also allows to add a reference to a dll. Also, there are quite a few built-in functions, similar to those in Crystal Reports. Although, if you have a Crystal Reports background and are switching to SSRS reports, some things will require getting used to. For example, to display current page number you would need to place a textbox control in the report's footer, go into expressions for that textbox and code it there instead of just dragging and dropping as it is done in Crystal Reports. This is what the expression for something like "Page 2 of 5" would look like:

="Page " & Globals!PageNumber & " of " & Globals!TotalPages

SSRS Development

To develop SSRS, you need to have BIDS (Business Intelligence Development Studio) installed. It can be part of SQL Server 2008 install.

Once you have it, you can create a couple of different types of projects: Report Server Project and Report Server Project Wizard. My preference is the Report Server Project, because it allows for more customization.

Before you begin designing and developing a new SSRS report, you have to create a DataSource. If you are planning to use this datasource in more than one report, make it shared.

Once you are done creating a datasource, you will have to create a dataset that you will use with the report. Here is the confusing part: you can't create a dataset without having a report, so you have to add a report to your project first and then create a dataset based on the datasource you created earlier. When creating a dataset, SSRS allows you to either type your SQL into a text field or you can choose the option to enter a stored procedure name. I personally prefer using stored procedures, since they allow to do much more than a plain SQL statement.

Let's create a simple report consisting of a table and a header. The header will contain the report name and will be placed in the header of the report; the data will be displayed in a table and will be placed in the body of the report. In order to do that, we'll drag a textbox control from the toolbox and position it within the header section and type a name for the report in it; then, we'll drag a table control from the toolbox and put it in the body section of the report. Once that's done, let's specify what data will be displayed in each table column. Assume that we are displaying customer info from Northwind database, we'll have 3 columns: First Name, Last Name, and Phone Number.

The table control will display little buttons in each table column for you to choose what data will be feeding this column, such as First Name, Last Name, or Phone Number in our case. Let's display First Name in the first column, Last Name in the second column, and Phone Number in the third column, and give those columns appropriate headings. Now the report is ready and you can run it by clicking the Preview tab. Optionally, you may add a page number in the footer and a date of last execution of the report in the header.

To display the execution date and time, simply add a textbox to the report that will display this information, right-click on the textbox and choose Expressions; in the expression text area enter the following code:

= Globals!ExecutionTime

This will display the date and time when the report was last executed in a General Date format (something like 1/26/2011 11:15:05 AM).

String Manipulation in .NET

2010-11-15T22:22:00.000-05:00

String is one of the most frequently used data types in programming. There are quite a few string functions out there and all of those functions are implemented differently in different programming languages. I am going to show here how this is done in .NET Framework.
In the example below I am going to demonstrate the use of StringBuilder class. The below example receives a string as a parameter and then reverses it:
private string ReverseString(String str)
{
    if (str != string.Empty)
    {
        StringBuilder sb = new StringBuilder();
        for (int i = str.Length - 1; i >= 0; i--)
        {
            sb.Append(str.Substring(i, 1));
        }
        str = sb.ToString();
    }
    return str;
}

Technorati Tags: .NET,C#,StringBuilder,String Manipulation

Here is another example that accepts a string, splits it, and then reverses the order of words in that string:
private void ReOrderString()
{

string str = "Token A#$%@&Token B#$%@&Token C#$%@&Token D#$%@&Token E";
string[] Split = str.Split(new string[] { "#$%@&" }, StringSplitOptions.None);
    StringBuilder sb = new StringBuilder();
    for (int i = Split.Length - 1; i >= 0; i--)
    {
        sb.Append(Split[i]);
        if (i > 0)
            sb.Append("#$%@&");
    }
    lblOriginalString.Text = "Token A#$%@&Token B#$%@&Token C#$%@&Token D#$%@&Token E";
    lblProcessedString.Text = sb.ToString();
}

Technical Interview: Frequently Asked Questions & Answers

2010-07-14T12:40:00.024-04:00

Most of the time, when applying for software development jobs, be prepared to answer the following questions:
1. General Programming Questions:

What is the difference between passing parameter by value versus passing it by reference?
What is boxing / unboxing?
What is implicit conversion?
What is explicit conversion?
Late Binding vs. Early Binding in VB.NET

2. OO Questions:

What are the main concepts of Object Oriented development?
What is an Abstract Class?
What is an Interface?
What is Reflection?
What design patterns do you know?
What is the difference between value types vs. reference types?

3. SQL Questions:

How do you join two tables (SQL)?
What are the differences between different types of join?
What is UNION?

4. HTML Questions:

How do you make a table cell that runs across several columns?
How do you make a table cell that spans across multiple rows?

OO Answers:
1. Object-oriented programming (OOP) is a programming paradigm that uses "objects" – data structures consisting of data fields and methods together with their interactions – to design applications and computer programs. Programming techniques may include features such as data abstraction, encapsulation, modularity, polymorphism, and inheritance.

2. Abstract classes are closely related to interfaces. They are classes that cannot be instantiated, and are frequently either partially implemented, or not at all implemented. One key difference between abstract classes and interfaces is that a class may implement an unlimited number of interfaces, but may inherit from only one abstract (or any other kind of) class. A class that is derived from an abstract class may still implement interfaces. Abstract classes are useful when creating components because they allow you specify an invariant level of functionality in some methods, but leave the implementation of other methods until a specific implementation of that class is needed. They also version well, because if additional functionality is needed in derived classes, it can be added to the base class without breaking code.

An abstract class is denoted in Visual Basic by the keyword MustInherit. In C#, the abstract modifier is used. Any methods that are meant to be invariant may be coded into the base class, but any methods that are to be implemented are marked in Visual Basic with the MustOverride modifier. In C#, the methods are marked abstract. The following example shows an abstract class:

' Visual Basic
Public MustInherit Class WashingMachine

Sub New()

' Code to instantiate the class goes here.

End sub

Public MustOverride Sub Wash
Public MustOverride Sub Rinse (loadSize as Integer)
Public MustOverride Function Spin (speed as Integer) as Long

End Class

// C#
abstract class WashingMachine
{
    public WashingMachine()
   {
         // Code to initialize the class goes here.
    }
    abstract public void Wash();
    abstract public void Rinse(int loadSize);
    abstract public long Spin(int speed);
}

In the above example, an abstract class is declared with one implemented method and three unimplemented methods. A class inheriting from this class would have to implement the Wash, Rinse, and Spin methods. The following example shows what the implementation of this class might look like:

' Visual Basic
Public Class MyWashingMachine
                 Inherits WashingMachine

Public Overrides Sub Wash()

    ' Wash code goes here

End Sub

Public Overrides Sub Rinse (loadSize as Integer)

' Rinse code goes here

End Sub

Public Overrides Function Spin (speed as Integer) as Long

' Spin code goes here

End Sub

End Class

// C#
class MyWashingMachine : WashingMachine
{
    public MyWashingMachine()
   {
    // Initialization code goes here.
   }

    override public void Wash()
   {
        // Wash code goes here.
    }

    override public void Rinse(int loadSize)
    {
        // Rinse code goes here.
    }

    override public long Spin(int speed)
    {
        // Spin code goes here.
    }
}

When implementing an abstract class, you must implement each abstract (MustOverride) method in that class, and each implemented method must receive the same number and type of arguments, and have the same return value, as the method specified in the abstract class.

3. An interface contains only the signatures of methods, delegates or events. The implementation of the methods is done in the class that implements the interface, as shown in the following example:

interface ISampleInterface
{
    void SampleMethod();
}

class ImplementationClass : ISampleInterface
{
    // Explicit interface member implementation:

    void ISampleInterface.SampleMethod()
    {
        // Method implementation.
    }

    static void Main()
   {
        // Declare an interface instance.

        ISampleInterface obj = new ImplementationClass();

        // Call the member.
        obj.SampleMethod();
    }
}

Remarks
An interface can be a member of a namespace or a class and can contain signatures of the following members:
•Methods
•Properties
•Indexers
•Events

An interface can inherit from one or more base interfaces.
When a base type list contains a base class and interfaces, the base class must come first in the list.

A class that implements an interface can explicitly implement members of that interface. An explicitly implemented member cannot be accessed through a class instance, but only through an instance of the interface, for example:

For more details and code examples on explicit interface implementation, see Explicit Interface Implementation (C# Programming Guide).

Example
The following example demonstrates interface implementation. In this example, the interface IPoint contains the property declaration, which is responsible for setting and getting the values of the fields. The class Point contains the property implementation.

// keyword_interface_2.cs
// Interface implementation
using System;

interface IPoint
{
// Property signatures:
    int x { get; set; }
    int y { get; set; }
}

class Point : IPoint
{
    // Fields:
    private int _x;
    private int _y;

// Constructor:
public Point(int x, int y)
{
    _x = x;
    _y = y;
}
// Property implementation:
public int x
{
    get
    {
        return _x;
    }
    set
    {
        _x = value;
    }
}

public int y
    {
        get
        {
            return _y;
        }
set
        {
            _y = value;
        }
    }
}

class MainClass
{
    static void PrintPoint(IPoint p)

    {
        Console.WriteLine("x={0}, y={1}", p.x, p.y);
    }
    static void Main()
    {
        Point p = new Point(2, 3);
        Console.Write("My Point: ");
        PrintPoint(p);
    }
}

4. Design Patterns: check this MSDN resource: http://msdn.microsoft.com/en-us/magazine/cc301852.aspx

SQL Answers:
1 & 2. SQL joins are used to query data from two or more tables, based on a relationship between certain columns in these tables. Different SQL JOINs:
•JOIN: Return rows when there is at least one match in both tables
•LEFT JOIN: Return all rows from the left table, even if there are no matches in the right table
•RIGHT JOIN: Return all rows from the right table, even if there are no matches in the left table
•FULL JOIN: Return rows when there is a match in one of the tables

SQL INNER JOIN Keyword
The INNER JOIN keyword return rows when there is at least one match in both tables.

SQL INNER JOIN Syntax
SELECT column_name(s) FROM table_name1
INNER JOIN table_name2 ON table_name1.column_name = table_name2.column_name

SQL LEFT JOIN Keyword
The LEFT JOIN keyword returns all rows from the left table (table_name1), even if there are no matches in the right table (table_name2).

SQL LEFT JOIN Syntax

SELECT column_name(s) FROM table_name1
LEFT JOIN table_name2 ON table_name1.column_name=table_name2.column_name

PS: In some databases LEFT JOIN is called LEFT OUTER JOIN.

SQL RIGHT JOIN Keyword
The RIGHT JOIN keyword Return all rows from the right table (table_name2), even if there are no matches in the left table (table_name1).

SQL RIGHT JOIN Syntax
SELECT column_name(s) FROM table_name1
RIGHT JOIN table_name2 ON table_name1.column_name = table_name2.column_name

PS: In some databases RIGHT JOIN is called RIGHT OUTER JOIN.

SQL FULL JOIN Keyword
The FULL JOIN keyword return rows when there is a match in one of the tables.

SQL FULL JOIN Syntax
SELECT column_name(s) FROM table_name1
FULL JOIN table_name2 ON table_name1.column_name = table_name2.column_name

3. UNION
The UNION operator is used to combine the result-set of two or more SELECT statements.

Notice that each SELECT statement within the UNION must have the same number of columns. The columns must also have similar data types. Also, the columns in each SELECT statement must be in the same order.

Note: The UNION operator selects only distinct values by default. To allow duplicate values, use UNION ALL.

SQL UNION Syntax
SELECT column_name(s) FROM table_name1
UNION
SELECT column_name(s) FROM table_name2

SQL UNION ALL Syntax
SELECT column_name(s) FROM table_name1
UNION ALL
SELECT column_name(s) FROM table_name2

Note: The column names in the result-set of a UNION are always equal to the column names in the first SELECT statement in the UNION.

SQL Server Keyboard Shortcuts

2010-04-15T11:57:00.000-04:00

SQL Server Keyboard Shortcuts from Microsoft

SQL Server 2005 Query Analyzer shortcuts

Visual Studio 2008 Cheet Sheet

2010-04-14T14:36:00.056-04:00

The other day I searched for a keyboard shortcut reference for Visual Studio 2008. After I saw the list of all the different shortcuts, I compiled a list of Visual Studio 2008 keyboard shortcuts for tasks that I use most frequently:

F5	Start your project in debug mode
F7 & Shift-F7	Show the code windows & show the designer window
Alt-Enter or F4	Show the properties panel for a selected object
F6 / Shift-F6 / Ctrl-Shift-B	Build Solution / Build Project / Build Solution
Shift-Alt-C	Add a new class to the project
Ctrl-Shift-A / Alt-Shift-A	Add a new item to your project / add an existing item to your project
Ctrl-K + Ctrl-C	Comment a selected block of code
Ctrl-K + Ctrl-U	Uncomment a selected block of code
Ctrl-M + Ctrl-O / Ctrl-M + Ctrl-P	Collapse all code to definitions / Expand all code (stop collapsing)
Ctrl-K + Ctrl-K	Toggle code bookmark
Ctrl-K + Ctrl-N	Go to next bookmark
Ctrl-K + Ctrl-P	Go to previous bookmark
Ctrl-Shift-Tab	Scroll backwards through open windows
F9	Set or remove a breakpoint
F12	Go to definition
Shift-F12	Display all references

Below are some of the VS2008 Keyboard Shortcuts Cheat Sheets that originally came up in my search:

Cheat Sheet with Key Images

22 Visual Studio Short Keys and 6 Short-cut Ways to Custom Jobs: A List of Tips and Tricks

Visual C# 2008 Keybinding Reference Poster

ASP.NET AJAX Date Picker

2010-01-14T22:39:00.011-05:00

Recently, while working on my Tai Chi club’s website, I realized that my club’s website is lacking the capability of scheduling a Tai Chi class (or any other type of event for that matter). In order to schedule any type of event, I would need to specify that event’s date and time, location, and maybe some kind of description or explanation of what’s going to be happening during that event. So, I started looking at different ways to create a Date Picker. After some research, I found out that it is very easily achieved with Ajax Control Toolkit, which provides CalendarExtender control.

The CalendarExtender control is designed to extend a TextBox. Its default behavior prompts the end user to pick a date from a calendar when the user clicks inside a textbox associated with the CalendarExtender.

This is what it looks like:
It is also possible to add a button to the right of the textbox and have the calendar popup whenever the user clicks that button (all you need to do is specify the button's ID as value of PopupButtonID property).

To customize the look of the popup calendar, add all or some of the following classes to your stylesheet and customize them appropriately:

To achieve the look above, I added the following class to my stylesheet:

.ajax__calendar_active
{
border: solid 2px green;
font-weight: bold;
}

and then in my page’s Page_Load event added the following line of code:

this.CalendarExtender1.SelectedDate = DateTime.Today;

.ajax__calendar_container
you can change the style of outer container of calendar control. Outer container holds the .ajax__calendar_header, .ajax__calendar_body, .ajax__calendar_footer as child container css classes.

.ajax__calendar_header
This css class holds the previous arrow, next arrow and current Month, Year. Child Css Classes are .ajax__calendar_prev, .ajax__calendar_next, .ajax__calendar_title.

.ajax__calendar_prev
This class is associated with an element that displays the left side arrow to view the previous month, year or decade based on the current view of calendar.

.ajax__calendar_title
This class is associated with an element that displays the month name, year or decade range according to the current view of the calendar control.

.ajax__calendar_next
This class is associated with an element that displays the right side arrow to view the next month, year or decade based on the current view of calendar.

.ajax__calendar_body
It is a container of the elements for displaying the different views of calendar such as month view, year view and day view. This class holds the .ajax__calendar_days, .ajax__calendar_months and .ajax__calendar_years as child css classes

.ajax__calendar_days
It changes the look of day view of month. Child Css Classes are .ajax__calendar_dayname and .ajax__calendar_day.

.ajax__calendar_dayname
It changes the look of day name at the top of day view of month.

.ajax__calendar_day
This class is associated with the day layout of month.

.ajax__calendar_months
It controls the month layout of month view. Child Css class is .ajax__calendar_month.

.ajax__calendar_month
It controls the look and feel of month names of month view.

.ajax__calendar_years
This class controls the layout of year view of calendar control. Child css class: .ajax__calendar_year.

.ajax__calendar_year
It changes the look and feel of years in the year layout of year view.

.ajax__calendar_footer
It is associated with Footer container that holds the current date.

.ajax__calendar_today
It displays the current date in the footer container of calendar control.

.ajax__calendar_hover
Dynamic color behavior onmouseover can be modified by using this class. It can be used with .ajax__calendar_title, .ajax__calendar_day, .ajax__calendar_month, .ajax__calendar_year, .ajax__calendar_today to change the mouse over behavior.

.ajax__calendar_active
It sets the style of currently selected date.

.ajax__calendar_other
It sets the style of day, month name or year that is outside the current view e.g. days that don’t belong to the currently visible month.

Passing Parameter to a Subreport

2009-02-18T09:52:00.003-05:00

A few days ago I was revising my application and made some modifications. One of the modifications were that now all of my subreports required an additional parameter, which was not required for the main report. The SetParameterValue(parameterName, parameterValue) method did not work, because it only works with main report object and can't be used with subreports. So, this is what I did to make it work:

1. I included additional parameters in the main report and then linked them to their corresponding counterparts in my subreports.

2. After that was done, I only had to pass their values to the main report using the SetParameterValue(parameterName, parameterValue) method.

Everything worked after I did that, which was a big relief for me, considering my deadlines :)

Passing Parameter to Crystal Report

2008-08-05T14:32:00.014-04:00

Recently, I was developing a pretty sophisticated Crystal Report that included multiple sub-reports and used multiple stored procedures as data sources. All of those stored procedures accepted the same parameter, which made my life a little easier, since I only had to deal with one parameter that I needed to pass to my Crystal Report.

In order for all sub-reports to be able to recognize the parameter, which I am passing to the main report, I had to link all of my sub-reports to the main report using that parameter.

In order to link a sub-report to the main report, the following actions should be performed:

To link a subreport to the data in the primary report

If you are creating a new subreport or importing an existing report as a subreport, from the Insert menu, click Subreport. Choose or create a report and click the Link tab.
- or -

If you have already placed a subreport in the primary report, but did not create a link at setup, navigate to the Subreport Links dialog box by choosing Subreport Links from the Edit menu.

The Subreport Links dialog box appears.
Choose the subreport you want to link from the For subreport list (if it is not already selected).
Select the field you want used as a link field in the primary (containing) report from the Available Fields list.
Click the > arrow.
The field is added to the "Field(s) to link to" list box, and is now selected as a link field.
Repeat steps 3 and 4 for each additional link, as desired.
Use the Field link section (which will only appear if you have selected a link field) to set up the link for each link field:
- Select the field you want linked to the primary report from the "Subreport parameter field to use."
- Select the "Select data in subreport based on field" check box on and select a field from the adjacent drop-down list to organize the subreport data based on a specific field (this is the quick equivalent of using the Select Expert). If nothing is specified here, the subreport will adopt the organization of the primary report.
Click OK.

When you run the report, the program will coordinate the data in the primary report with the data in the subreport.

Below is the code that I used to pass my parameter to the Crystal Report and then display it in PDF format to the end-user:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

GenerateReport(Session("EmpId"))

End Sub

Private Sub GenerateReport(ByVal EmpId As Integer)

Dim theReport As New ReportDocument
theReport.FileName = "C:\myProject\Reports\myReport.rpt"
theReport.SetDatabaseLogon(PCON.APP.UserName, _
PCON.APP.Pass, _
PCON.APP.db_Server, _
PCON.APP.dbName)

'Set the required parameter for Crystal Report
theReport.SetParameterValue("@Id", EmpId)

'Now, present report in PDF format
theReport.ExportToHttpResponse ( _

ExportFormatType.PortableDocFormat, _
Response, _
False, _
"ExportedReport")

End Sub

Character Counter

2008-03-22T23:19:00.022-04:00

Recently I was developing a webform (asp.net) where the user could submit his feedback, and one of the requirements was that the user should not enter more than a set number of characters in his message, so I thought it would be real nice for the end user to know how many more characters he still can type until the maximum limit is reached.

In order to allow that functionality, I created a asp.net multiline textbox for text input and an html readonly text field (for displaying number of characters until the maximum).

Then, I created a Javascript function and called it every time the contents of the multiline textbox changed (onKeyUp and onChange events).

Below is the code:

<html>
<head>

<script language="JavaScript">


function CountChars(text,long)
{
   var maxlength = new Number(long);
   var myLength = text.value.length;
   document.forms[0].Counter.value = maxlength - myLength;
   if (myLength > maxlength){
      text.value = text.value.substring(0,maxlength);
   }
}

</script>

</head>
<body>

<form id="Form1" runat="server">

<asp:Textbox mode="multiline" id="txtMessage" runat="server" /><br />

<input type="text" name="Counter" readonly="readonly" />

</form>

</body>
</html>

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Util.SetTextBoxPropertiesFull(txtMessage, True)
End Sub

and then, in the SetTextBoxPropertiesFull method I had the following two lines of code that did the work:

txt.Attributes.Add("onKeyUp", "CountChars(this," & txt.MaxLength & ")")
txt.Attributes.Add("onChange", "CountChars(this," & txt.MaxLength & ")")

Another handy code snippet is as follows:

txt.Attributes.Add("onfocus", "this.className='myStyle1'")
txt.Attributes.Add("onblur", "this.className='myStyle2'")

where myStyle1 and myStyle2 are names of css classes defined in the stylesheet.

Converting ASP.NET to PDF

2007-03-29T13:02:00.000-04:00

I probably wouldn't be wrong if I said that most developers every now and then are tasked to present specific data contained in a webpage as a PDF document. There are two ways to do it:

using the functionality of CrystalReportViewer's toolbar - this toolbar provides a button, which does exactly that. However, to use this approach you would have to actually display the crystal report on the page.

programmatically convert the Crystal Report object into a PDF document using the Crystal Reports API

Below is the code for the second approach:

Dim report As CrystalReport1 = New CrystalReport1
SqlDataAdapter1.Fill(DataSet11)
report.SetDataSource(DataSet11)
report.ExportToHttpResponse _
(ExportFormatType.PortableDocFormat, _
Response, _
False, _
"ExportedReport")

Crystal Reports with ASP.NET

2007-03-27T03:24:00.001-04:00

When it comes to developing a report for an ASP.NET application, one might find that there is very little information available on how it's done using Crystal Reports.

Visual Studio 2003 comes with a built-in version of Crystal Reports (CR 9). Using that built-in version of Crystal Reports might save you some money, since it's a part of VS 2003, however, from the Crystal Reports design prospective it is much more convenient to use a stand-alone version of Crystal Reports.

The latest version of Crystal Reports at the time of writing this post is Crystal Reports XI, which provides some new features, not available in previous versions (see the www.businessobjects.com website for more info), so in my last development I used that version of Crystal Reports.

In order for the report to display as a webpage, VS 2003 provides CrystalReportViewer control. This is how it works:

Instantiate the DataSet object
Dim ds As New DataSet ds = GetDataForReport() 'some method that retrieves data for the report Instantiate the ReportDocument object: Dim rpt As New ReportDocument 'set the ReportObject as the report you want to display rpt = New CrystalReport1 'Define the datasource of your report rpt.SetDataSource(ds) 'define your report as a reportsource for the crystalreportviewer CrystalReportViewer1.ReportSource = rpt
Below is C# version of this code:
DataSet ds = new DataSet(); ReportDocument rpt = new ReportDocument(); rpt = new CrystalReport1(); rpt.SetDataSource(ds); CrystalReportViewer1.ReportSource = rpt;

In order for this code to work, the following namespaces must be imported/used:

CrystalDecisions.CrystalReports.Engine
CrystalDecisions.Shared
CrystalDecisions.Web.Design

The following namespaces should be used only if you are planning to convert the report into a PDF, Word, or Excel format.

CrystalDecisions.Shared.ExportDestinationType
CrystalDecisions.Shared.ExportFormatType
CrystalDecisions.Shared.ExportDestinationOptions