Session State

ASP.NET allows you to save values by using session state — which is an instance of the HttpSessionState class — for each active Web-application session.

Session state is similar to application state, except that it is scoped to the current browser session. If different users are using your application, each user session will have a different session state. In addition, if a user leaves your application and then returns later, the second user session will have a different session state from the first.

Session state is structured as a key/value dictionary for storing session-specific information that needs to be maintained between server round trips and between requests for pages.

You can use session state to accomplish the following tasks:

• Uniquely identify browser or client-device requests and map them to an individual session instance on the server.

• Store session-specific data on the server for use across multiple browser or client-device requests within the same session.

• Raise appropriate session management events. In addition, you can write application code leveraging these events.

Once you add your application-specific information to session state, the server manages this object. Depending on which options you specify, session information can be stored in cookies, on an out-of-process server, or on a computer running Microsoft SQL Server.