Calling a javascript function from a response.write(string.format())

Hi guys ! I made a function in js in my webform and i would like to call it with a certain command
 This is the function name: MailBoxPoistion
And this is what i have tried to do:
 esponse.Write(string.Format("<script type='text/javascript'>MailboxPosition())</script>"));
After clicking a button in a diffrent page my webform is been directed and then I would like the above command to
be executed but from some reason it doesnt seem that the js  function that i wrote in the the aspx part of my webform
 is recogenized.
 
what is the correct syntax to do that?
 
thanx a lot
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