Friday, September 10, 2010

ASP.Net Custom Server Control

by Emmaneale Mendu, Web Developer

In this post - we look at how to create a custom server control and Test the control in Web Page.

To Create the custom control(Microsoft Visual Studio 2008)
Note:: Click on the image if they are not clear
  1. From the File Menu select New Project

  2. Now you see New Project Window, Select Web in Project types section, ASP.NET Server Control in Templates Section. Change Desire Name "SampleCustomControl" as shown below,

  3. Change ServerControl.cs to WelcomeLoginControl.cs as shown below

  4. Click Yes

  5. Delete the code and change it to as shown below

  6. using System;
    using System.Collections.Generic;
    using System.ComponentModel;
    using System.Linq;
    using System.Text;
    using System.Web;
    using System.Web.UI;
    using System.Web.UI.WebControls;

    namespace aspWelcomeLabel
    public class WelcomeLoginControl : System.Web.UI.WebControls.WebControl, INamingContainer
    //Label Control Fields
    protected TextBox txtFirstName = new TextBox();
    protected TextBox txtSecondName = new TextBox();

    //TextBox Control Fields
    protected Label lblFirstName = new Label();
    protected Label lblSecondName = new Label();
    protected Label lblWelcome = new Label();

    //Button and Required Fields
    protected Button btnSubmit = new Button();
    protected RequiredFieldValidator rfFirstName;
    protected RequiredFieldValidator rfSecondName;

    public override ControlCollection Controls
    return base.Controls;

    protected override void CreateChildControls()

    //Assign Properties to TextBox Controls
    txtFirstName.ID = "txtFirstName";
    txtSecondName.ID = "txtSecondName";
    lblWelcome.ID = "lblWelcome";

    //Assign Properties to Label Controls
    lblFirstName.Text = "First Name";
    lblSecondName.Text = "Last Name";

    //Assign Properties to Button and RequiredField validator Controls
    btnSubmit.Text = "Submit";
    btnSubmit.Click += new EventHandler(btnSubmit_Click);

    rfFirstName = new RequiredFieldValidator();
    rfSecondName = new RequiredFieldValidator();

    rfFirstName.ControlToValidate = txtFirstName.ID;
    rfSecondName.ControlToValidate = txtSecondName.ID;
    rfFirstName.ErrorMessage = "First Name is Required";
    rfSecondName.ErrorMessage = "Second Name is Required";

    Controls.Add(new LiteralControl("<br />"));
    Controls.Add(new LiteralControl("<br />"));
    Controls.Add(new LiteralControl("<br />"));

    private void btnSubmit_Click(object sender, EventArgs e)
    lblWelcome.Text = "Welcome " + txtFirstName.Text + " " + txtSecondName.Text;
  7. Open AsseblyInfo.cs
    Add this at the First Line
    using System.Web.UI;
  8. At the End of the Page add this
    [assembly: TagPrefix("SampleCustomControl", "AspSample")]
  9. And then Build it

  10. AssemblyInfo.cs looks like this

    using System.Reflection;
    using System.Runtime.CompilerServices;
    using System.Runtime.InteropServices;
    using System.Web.UI;

    // General Information about an assembly is controlled through the following
    // set of attributes. Change these attribute values to modify the information
    // associated with an assembly.
    [assembly: AssemblyTitle("aspWelcomeLabel")]
    [assembly: AssemblyDescription("")]
    [assembly: AssemblyConfiguration("")]
    [assembly: AssemblyCompany("BrownGreer PLC")]
    [assembly: AssemblyProduct("aspWelcomeLabel")]
    [assembly: AssemblyCopyright("Copyright © BrownGreer PLC 2010")]
    [assembly: AssemblyTrademark("")]
    [assembly: AssemblyCulture("")]

    // Setting ComVisible to false makes the types in this assembly not visible
    // to COM components. If you need to access a type in this assembly from
    // COM, set the ComVisible attribute to true on that type.
    [assembly: ComVisible(false)]

    // The following GUID is for the ID of the typelib if this project is exposed to COM
    [assembly: Guid("e6a12269-411b-40ef-8cb2-2a01393ecbc7")]

    // Version information for an assembly consists of the following four values:
    // Major Version
    // Minor Version
    // Build Number
    // Revision
    // You can specify all the values or you can default the Build and Revision Numbers
    // by using the '*' as shown below:
    // [assembly: AssemblyVersion("1.0.*")]
    [assembly: AssemblyVersion("")]
    [assembly: AssemblyFileVersion("")]
    [assembly: TagPrefix("aspWelcomeLabel", "aspSample")]

Test the Control in ASP.Net Web Page
  1. Create a New WebSite(Open File and New WebSite)
  2. Add .dll of SampleCustomControl to the Website Project to your toolbox
  3. Drag and drop the control to your page
  4. Run and See it Works, Dont Forget to leave your

  5. .aspx looks like this
    <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

    <%@ Register Assembly="aspWelcomeLabel" Namespace="aspWelcomeLabel" TagPrefix="aspSample" %>
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "">
    <html xmlns="">
    <head runat="server">
    <title>Untitled Page</title>
    <form id="form1" runat="server">
    <aspSample:WelcomeLoginControl ID="WelcomeLabel1" runat="server" />

  6. OutPut Looks Like this

  7. To Be Modified....


  1. Nice one and thanks for this helpful post. Great job.

  2. It's really good and Post more example in ASP.NET ....Thanks you ..........