First, I would like to suggest you to use the Client API, in order to get reference to the control (and the tabs) instead of the approach you attempt to use - document.getElementById
In addition, the approach which I can suggest you to use in order to achive the desired functionality is as follows :
- Use the MasterPage and a custom function, in order to get a reference to the RadTabStrip and expose it through that function :
tabStrip = $find(
"<%= RadTabStrip1.ClientID %>"
- In any of the content pages, you can use window.parent.getTabStrip(),in order to get a reference to the RadTabStrip and then access the needed Tab :
TabStrip = window.parent.getTabStrip();
tab1 = TabStrip.findTabByText(
In addition, in the attachment, you could find a simplified runnable project, demonstrating the behavior of the above suggested approach.
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