jquery / ajax / expression engine - set a custom member field within a safecracker form -

I am using jquery with the expression engine to submit an AJAX form, using the secure cracker module, here Documented:

Actually, my form allows members to vote. I want them to vote only once, so I set up a custom profile data field called "Voting", which I want to set after the submission of the form to "Truth." Is this possible? If so, then how?

SafeCracker has an extension hook that is called safecracker_submit_entry_end () , So that you can create an extension that uses that hook, then what you need to do in that hook method.

Hint: The extension hook is passed in the context of the SafeCracker object, which is not a document. So when you first test the extension, print the object so that you can see what's included in it:

  function safecracker_submit_entry_end ($ safecracker) {print_r ($ safecracker) ; Go out(); }   
 If you are unfamiliar with developing Extension Angle and using Database Class etc., then this is the second thing else. If you start the case then I can post some links to you.