Placeholder control, changed in 2.0 ? 1

[Kalisto]

Im trying to update a page for an old website buit in .net 1.1

In the old site, I can access a Placeholder simply by typing
PlaceHolder p = (PlaceHolder)FindControl("CorrectPlaceholder");

However, on the new site, this doesnt work, and the FindControl() method returns null.

If I look into the page I can see the placeholder I want, but I end up having to go throuhg 3 or 4 FindControl() steps to be able to access it.

Can anyone tell me how to get round this issue, so I only need the one FindControl() statement ?

And also why this has changed?

K

 

[jmeckley]

FindControl finds the control within the current control. it doesn't (in most cases) search sub controls for the control.

you could use a recursive function.

public static class PageUtil
{
   public T FindNestedControl<T>(Control parent, string id) where T : Control
   {
      var control = parent.FindControl(id);
      if(control != null)
      var typed_control = control as T;
      if(control != null) return control;
      parent.Controls.First(c=>FindNextedControl<T>(c, id));
   }
}

from the page you can call

var textbox = PageUtil.FindNestedControl<TextBox>(this, "foo");

Jason Meckley
Programmer
Specialty Bakers, Inc.

 

[Kalisto]

Not using 3.5, but I know what you are suggesting, thanks.

K