The ClientCallBack function is mandatory if you are using radconfirm(). As noted in the documentation and the demos, RadWindowManager's popups (radconfirm, radprompt, radalert) cannot block the execution thread like the standard browser popups (confirm, prompt, alert) - this is something that cannot be done with JavaScript. That is why with radconfirm and radprompt, we use a ClientCallBack function in which (after user's input) the logic should continue.
Greetings,
Georgi Tunev
the Telerik team
Do you want to have your say when we set our development plans?
Do you want to know when a feature you care about is added or when a bug fixed?
Explore the
Telerik Public Issue Tracking
system and vote to affect the priority of the items.