Hi,
I think the best way to handle a confirmation is to make a fuction in the client code with
OnClientClick event call.
Nevertheless you could do it in code behind by adding an attribute in your existing button as example:
btnDelete.Attributes.Add("Onclick", "return confirm('Are You Sure to Delete this Claim?')")
Please remember to mark the replies as answers if they help and unmark them if they provide no help.
Regards,
Algem