Access Session Variables in an ASP.NET Custom HttpHandler

If session state is required in your HTTP handler, you need to implement the IRequiresSessionState interface.

The IRequiresSessionState is a marker interface which is empty without any methods or elements in it and gives read/write access to Sessions. A Marker interface like this one just informs the runtime that a certain feature is to be enabled.

On the other hand, if you require only a read only access to Session, use the IReadOnlySessionState which is also a marker interface.

C#

public class MyHandler : IHttpHandler, IRequiresSessionState

{

    //  Use Session now

}

VB.NET

Public Class MyHandler

    Implements IHttpHandler, IRequiresSessionState

    '  Use Session now

End Class