The other major change in page lifecycle involves post back events and Web Forms. In ASP.NET 1.x, Web Forms automatically postback to their host page. That is, when a user submits a form, the form data is always submitted back to the page containing the original form. This design decision allows for easy storage of control state, but limits the ability of the developer to perform more complex operations.

In ASP.NET 2.0, Web Form controls have a new property that lets the developer decide where the form data should be sent on a submit action. In most cases, the postback mechanism will be desired, and it is therefore still the default. However, if the developer wants to post data to a different form, it is now possible.