Custom WebControl with OnClick event

[Tomasz J]

Hello Developers,

How do create a custom WebControl (not UserControl), exposing OnClick event?
I reviewed countless examples found by Google, but came across nothing
helpful.
Below I attach what I got so far.

Thank you for any hints.

Tomasz J
using System;
using System.Collecti ons.Generic;
using System.Componen tModel;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.W ebControls;

[DefaultProperty ("Text")]
[ToolboxData("<{ 0}:MyButton runat=\"server\ "></{0}:MyCloseButt on>")]
public class MyButton : WebControl
{
[Bindable(true)]
[Category("Appea rance")]
[DefaultValue("" )]
[Localizable(fal se)]
public string Text
{
get
{
String s = (String)ViewSta te["Text"];
return ((s == null) ? String.Empty : s);
}

set
{
ViewState["Text"] = value;
}
}

// should I use: Attributes.Add( "OnClick",
Page.Clientscri pt.GetPostBackE ventReference(t his, ID.ToString))

[Category("New") , Browsable(true)]
public event EventHandler Click;

protected void OnClick(EventAr gs e)
{
if (Click != null) {
Click(this, e);
}
}

protected override void RenderContents( HtmlTextWriter output)
{
output.WriteBeg inTag("div");
output.WriteAtt ribute("style", "cursor:pointer ;");
output.WriteAtt ribute("onclick ", "alert('test'); ");
output.Write(Ht mlTextWriter.Ta gRightChar);
output.Write(Te xt);
output.WriteEnd Tag("div");
}
}

[Peter Bucher [MVP]]

Hallo TomaszJ

How do create a custom WebControl (not UserControl), exposing OnClick
event?
I reviewed countless examples found by Google, but came across nothing
helpful.

Any Control beside the Button itself uses clientside Javascript to do a
PostBack and raise Events.
If you want to create a Button like control that have all the
functionalities like CommandName and CommandArgument , you have to derive
from IButtonControl And IPostBackEventH andler, or directly from the button
class.
Otherwise, you have to handle the whole thing with Javascript.
The GetPostBackRefe rence Methode gives you a return value, that you must bin
to a hyperlink target or an clientside eventhandler of an Html Control
(<Control>.Attr ibutes.Add(<att ribute>, <postback reference>)).

Such a control have to implement the IPostBackEventH andler interface to
raise the event.

A good example of an control that handle an event that raised by javascript
is the Link Button:
-
http://msdn2.microsoft.com/en-us/lib...on(VS.80).aspx

An example for an very, very basic button control as customcontrol can be
found here (only in german):
-
http://msdn2.microsoft.com/de-de/lib...er(VS.80).aspx

The GetPostBackRefe renceMethode can found in the Page.ClientScri pt class:
-
http://msdn2.microsoft.com/en-us/lib...pt(VS.80).aspx
HTH

--
Gruss, Peter Bucher
Microsoft MVP - Visual Developer ASP / ASP.NET, Switzerland
http://www.aspnetzone.de/ - ASP.NET Zone, die ASP.NET Community
http://www.aspnetzone.de/blogs/peterbucher/ - Auf den Spuren von .NET

[Peter Bucher [MVP]]

Hi Tomasz again

I have forgot a detail ;-)
You can view the code from the LinkButton, or any other control with .NET
Reflector.
- http://www.aisto.com/roeder/dotnet/

--
Gruss, Peter Bucher
Microsoft MVP - Visual Developer ASP / ASP.NET, Switzerland
http://www.aspnetzone.de/ - ASP.NET Zone, die ASP.NET Community
http://www.aspnetzone.de/blogs/peterbucher/ - Auf den Spuren von .NET

[Tomasz J]

Thank you, I got it working.
I did not expect it to that trivial.

Tomasz J