checking if session variable is null returns nullreferenceexception

c#, session

Solution

edit: I also tried

if(Session["object"] != null)

Note that the code in your edit is not checking that `Session` is not null. If it is null, the expression `Session["object"]` will still cause the error because this is searching the session instance for the "object" key - so if you think about it logically you are looking for a key in an uninstantiated object, hence the null reference exception. Therefore you need to verify `Session` has been instantiated before checking if `Session["object"]` is null:

if (Session != null)
{
    if(Session["object"] == null)
    {
         Session["object"] = GetObject();
         return Session["object"] as List<object>;
    }
    else
    {
        return Session["object"] as List<object>;
    }
}
else
{
    return null;
}

Problem

I have a List of objects stored in a session variable. But when I check to make sure the session variable is not null, it gives me a `NullReferenceException: Object reference not set to an instance of an object`. ``` if(Session["object"] == null) //error occurs here { Session["object"] = GetObject(); return Session["object"] as List<object>; } else { return Session["object"] as List<object>; } ``` How can I check if the Session is null? edit: I also tried ``` if(Session["object"] != null) ```

Original source