I am not sure what you mean. Do you want 3 buttons that when clicked will change the value of the text box AND then call server side code or do you want 3 buttons that will change the text box and then a 4 button that will post back to the server??
Read this if you want to know how to get a correct reply for your question:
^^Took that from planoie's profile^^
^^Modified text taken from gbianchi profile^^
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