what are the differences between IsPostBack and ViewState?
Posted on 2008-01-28
I thought I understood the differeces between IsPostBack and ViewState. But, for some reason I am getting the two mix up. I understand that one will use IsPostBack when a page or object contains data and it is sent back to the server for a reload. The IsPostBack is supponsed to privent handler of code to not execute again if the page has been load once. Now, for the ViewState, what I think it does is to wrape an object on a hidden field an hashed it to maintain its information since HTTP is a stateless protocol.
Does the ViewState wrapes a single object or the entire page? Does the ViewState caches the data, therefore, improving pefomance? Is this caching perfored on the server side? What performance impacts are there on the server when IsPostBack or ViewState is used. Is there a time when to many objects, using ViewState, will dicrease the server performance?
Please, can some one explain in more depth the diffences between the IsPostBack and ViewState? When should one be used over the other? Can they be used together? I am not totally clear?