Ashx, the page generally does not support session method. You must add two interfaces. To access the session.

Ashx, the page generally does not have a method for session. You must add two interfaces (ihttphandler and irequiresesstionstate ). To access the session.

Interface 1. ihttphandler: implements two methods: processrequest and isresuable;

Isreusable: This attribute obtains a Boolean value indicating whether another request can be processed using this HTTPProgramInstance

Processrequest: This method processes HTTP requests.

Interface 2. irequiresesstionstate is an empty interface (marking interface) that does not implement any method.