how to iterate over controls in page to set properties

using: asp.net 2.0 - [vs2005]

I have a page with a master template named "MasterPage.master" and want to iterate over all of the controls in the Page to set a property.

I tried using this in the Page Unload event:

VB Code:

Dim ctlControl As System.Web.UI.WebControls.WebControl
        For Each ctlControl In Page.Controls
            ctlControl.Enabled = False
        Next

but this gives an exception:

Unable to cast object of type 'ASP.masterpage_master' to type 'System.Web.UI.WebControls.WebControl'.

I tried removing the Master template
but I still get same error but instead of 'ASP.masterpage_master' it
refers to Literal Control.

Am I missing something here?

Please help. Thanks in advance.

Page.Controls returns a ControlCollection - Page is extends TemplateControl which in turn extends Control, whereas your for...each uses an object of WebControl. As for the exception, it details the casting problem - it can't cast from LiteralControl (extends Control) to WebControl.

The safest way to handle a loop of this sort is to use an object of type "System.Web.UI.Control" for your For Each loop, i.e.:

Code:

---

Dim myControl As Control
For Each myControl in Page.Controls

---

But I get the same error when I use the sample code that you show.

I'm thinking this has something to do with the Master template.

Hi,
I´m no expert but have you tried puting it in a try/catch? Without catching the exeption.

Dim ctlControl As System.Web.UI.WebControls.WebControl
For Each ctlControl In Page.Controls
Try
ctlControl.Enabled = False
Catch ex As Exception

End Try

Next