The Controls collection cannot be modified...

VerbatimBOT · October 22nd, 2007, 07:45 AM

Hi all!
I'm having troubles with dynamically adding some attributes to IMG tag within the asp:Panel.

Here is the code:

Code:

<asp:Panel ID="panelArea" runat="server">
  <table border="0" width="100%">
    <tr>
      <td>
        <asp:PlaceHolder ID="phArea" runat="server" />
      </td>
      <td>
        <img id='<%= "tabImg" + ClientID %>' src='<%= ImageUrlOpen %>' />
      </td>
    </tr>
  </table>
</asp:Panel>

The error I keep getting is The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).

Has anyone faced this problem earlier?
Thanks!

Aleksandar Dragosavac
Belgrade, Serbia

planoie · October 22nd, 2007, 09:18 AM

Don't use the ASP style <% %> code block. I see any reason you need these. Instead, you should use an ASP:IMAGE control.

What control are you trying to add the controls to? You state "within the asp:Panel" however, it looks from your code that you should be adding them to the "phArea" placeholder instead.

-Peter

VerbatimBOT · October 22nd, 2007, 09:43 AM

You're right!
I have replaced

Code:

<img id='<%= "tabImg" + ClientID %>' src='<%= ImageUrlOpen %>' />

with

Code:

<asp:Image ID="tabImg" runat="server" ImageUrl='<%# ImageUrlOpen %>' />

and it gives me no error. I don't know why was I insisted on html IMG tag instead of using asp:Image...

Yes, I will be adding dynamically controls to phArea (have a couple of methods for that).

Thanks a lot!

Aleksandar Dragosavac
Belgrade, Serbia