C# Possible unintended reference comparison

Question

When i try to check Session["userId"] != null why i get this message Possible unintended reference comparrison; to get value comparrison; cast left hand side to string Any suggestion....

Answer 1

Session[key] returns an object, not a string - you should be casting it to string rather than relying on implicit casting or ToString() functionality.

Answer 2

        if(Session["userId"]!=null)
        {

        }

works just fine for me