[SOLVED] Check if session item exists fails itself with object reference not set error

Check if session item exists fails itself with object reference not set error

I'm having problem regarding session items. Before I use them, I want to check if they exists, but using this codes gives me error:

If (Session("SomeSessionItem") Is Nothing) Then
...
End If

This is the error:

Object reference not set to an instance of an object.

I think Session("SomeSessionItem") tries to acquire the value of the session item. If the item doesn't exists then it throws exception. But how do I check if a session item exists before using them?

I have a page Home.aspx.
In the Home.aspx.vb, I instantiate a WebUserControl SomeControl.ascx. Note that in Home.aspx.vb event handler Page_Load I can use a condition to check session without getting an exception.
Inside SomeControl.ascx.vb I'm trying to access the session, here's where the exception occurs.

Solution

Does that work for you?

If (Session IsNot Nothing)
    Dim item as Object = Session("SomeSessionItem")
    If (item IsNot Nothing)
    ...
    End If
End If

Also, you may need to check HttpContext.Current.Session rather than simply Session if you're seeing the the following error:

Session does not exist in this context