// alert(sender.get_value());//to get the value, you can store the specific file name here for example
"your new image url here"
This code is built on top of the RadToolTipManager with ImageMap
online demo, so you should be able to easily incorporate it there as you have the online demos installed locally - you can find them in the LiveDemos folder in the RadControls installation. I also advise that you examine the demo carefully due to the large number of limitations of the image map.
As for your issue with AJAX - the OnAjaxUpdate event of the RadToolTipManager only updates it content and therefore other changes to the page are not sent to the client. This is a general situation with AJAX. If you insist on using server-side code you can place the image map in an update panel with updatemode set to conditional and call its update method in the code-behind, but I cannot guarantee that the tooltips will continue functioninig, since this way the control will be disposed and the handlers attached to the areas will be lost.
the Telerik team
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