Even though the solution is on the client-side, it should work just fine with a RadRating control that is set to autopostback, because the client-side event handler will be called just before the page is being sent to the server.
Still if you wish to completely escape the client-side code, then you will need to have a way to persist the old value of the RadRating control on the server side and in the OnRate
event handler you need to make the same checks and assignments as in the client-side approach.
Hope this helps.
the Telerik team
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