Ok managed to get the code working, as in no errors but it wont do a post back after ive confirmed when I click on the div?:
The problem is because __doPostBack is not defined. It's not defined because you didn't put any control on your page that is a an IPostBackEventHandler, like LinkButton is.
In order to Page.IsPostBack to be true, you have to either:
IPostBackEventHandler and, of course, put it on your pageIPostBackEventHandler on your page. One that doesn't do anything. Like a LinkButton.Either way ASP.NET will define the __doPostBack function at client side and your code will finally postback