State Management In ASP.NET
is something that seems essential for user-friendly interactive sessions. However, ASP.NET provides a workaround to this problem, such that session management becomes almost transparent. In short, information such as the state of controls on a Web Form (including data entered in text boxes or selections from drop-down lists) is stored in a hidden view state field that is part of the page generated by the server and passed to the user. Subsequent actions, such as triggering events that require server-side processing, like submitting form data, result in this information being sent back to the server; this is known as a post back operation. On the server, this information is used to repopulate the page object model allowing you to operate on it as if the changes had been made locally. You will see this in action shortly and examine the details.