<asp:RadioButtonList ID="T_selector" runat="server">
The ID you give the ASP control will change at runtime.
if (document.getElementById("T_selector").checked==false)
You need to change your hardcoded ID string to change at runtime using.
(document.getElementById('<%= T_selector.ClientID %>').checked==false)
or you can use the following if you have the Microsoft Ajax Library in your project.
($get ('T_selector').checked==false)
The id's you set for ASP controls are changed at runtime due to the server side compilation. This may seem confusing but for instance if you have a page which contains 2 user controls which both contain a textbox with id 'textName' then the document could not be well formed due to two ID's colliding, also the server would not be able to distinguish between the two on postback.
Hope this helps.
Fungus1487
Posting Pro in Training
459 posts since Apr 2007
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