How to handle events of controls created at run time?

[Lalit]

Hi,

My application has two methods which creates buttons at runtime. In one
method I am able to handle the events of the buttons created at run time, but
in other I am not.

The code structure is as follows:

page_load
{
...Do something
CreateFirstSetOfButtons()
}

private CreateFirstSetOfButtons()
{
// Create first set of buttons
for { i=1; i<5; i++)
{
LinkButton newButton1 = new LinkButton();
newButton1.Click += new EventHandler(this.Button1_Click);
}
... Do something
}

// Event handler of first set of buttons. The second buttons are created on
click of first buttons click.
private void Button1_Click(object sender, System.EventArgs e)
{
CreateSecondSetOfButtons();
}
private CreateSecondSetOfButtons()
{
// Create first set of buttons
for { i=1; i<2; i++)
{
LinkButton newButton2 = new LinkButton();
newButton2.Click += new EventHandler(this.Button2_Click); // This event
is never getting fired.
}
... Do something
}

private void Button2_Click(object sender, System.EventArgs e)
{
Response.Write("Hello");
}

On click of buttons created at page load I am able to catch the Click evet
of those buttons and the second set of buttons gets created. But when I click
on this second set of created buttons, the statement
Response.Write("Hello"); never gets executed.

An early resolution for the same will be really helpful.

Regards
Lalit

 

[Victor Garcia Aprea [MVP]]

Hi Lalit,

You can't create controls in response of a click event and expect these
controls to work ok on a postback. You need to create these controls earlier
so ASP.NET can find them in the control tree before getting to the event
firing stage. If you don't do this, when the event firing logic fires your
controls have not been created yet so i.e. there is no one to handle events.
Take a look at the docs regarding the page lifecycle to get a good grasp of
what fires when.

--
Victor Garcia Aprea
Microsoft MVP | ASP.NET
Looking for insights on ASP.NET? Read my blog:
My blog: http://clariusconsulting.net/vga
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