Object reference not set in asp.net

Question

if (Session["admin_uname"].ToString() == "")
{
    Response.Redirect("login.aspx");
}
else
{
    string userid = Session["admin_uname"].ToString(); 

}

i have wrote above code for sessions... but problem is if there is any session variable it was working properly

if session is not there it was not redirecting to login page and giving an error like

OBJECT REFERENCE NOT SET.

Almost all cases of NullReferenceException are the same. Please see "What is a NullReferenceException in .NET?" for some hints. — John Saunders
– John Saunders, Commented Aug 11, 2013 at 19:32

Raghubar · Accepted Answer · 2013-08-11 18:37:25Z

2

If there is no session exits then u will not able to compare anything. So check its Null or Not. This is how u check the session.

   if (Session["admin_uname"] == null)
    {
        Response.Redirect("login.aspx");
    }
    else
    {
        string userid = Session["admin_uname"].ToString(); 
    }

answered Aug 11, 2013 at 18:37

Raghubar

2,7981 gold badge23 silver badges31 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Rahul Tripathi · Accepted Answer · 2013-08-11 18:38:55Z

0

When you call ToString() on that null, you get the exception. So check for Null value too. You can try this:-

if (Session["admin_uname"].ToString() == "" || Session["admin_uname"].ToString() == Null)

answered Aug 11, 2013 at 18:38

Rahul Tripathi

173k33 gold badges292 silver badges341 bronze badges

Comments

Rahul · Accepted Answer · 2013-08-11 18:39:00Z

0

Check for nullity before you reference the object, like

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

// do something

answered Aug 11, 2013 at 18:39

Rahul

78.1k14 gold badges80 silver badges132 bronze badges

Comments

afzalulh · Accepted Answer · 2013-08-11 19:19:09Z

0

I would do like this:

if (Session["admin_uname"] != null || Session["admin_uname"].ToString() == "")
    Response.Redirect("login.aspx");

string userid = Session["admin_uname"].ToString();

answered Aug 11, 2013 at 19:19

afzalulh

7,9432 gold badges28 silver badges37 bronze badges

Comments

Joel Coehoorn · Accepted Answer · 2013-08-11 19:41:24Z

0

One more entry:

string userid = Session["admin_uname"] ?? "";
if (string.IsNullOrEmpty(userid))
{
    Response.Redirect("login.aspx");
}

answered Aug 11, 2013 at 19:41

Joel Coehoorn

418k114 gold badges582 silver badges820 bronze badges

Comments

Ashley Medway · Accepted Answer · 2014-05-21 14:42:09Z

0

You could use this:

if (String.IsNullOrEmpty(Session["admin_uname"].ToString()))
{
    Response.Redirect("login.aspx");
}
else
{
    string userid = Session["admin_uname"].ToString(); 
}

edited May 21, 2014 at 14:42

Ashley Medway

7,3197 gold badges54 silver badges73 bronze badges

answered Aug 11, 2013 at 18:43

Goran Štuc

5814 silver badges15 bronze badges

Collectives™ on Stack Overflow

Object reference not set in asp.net

6 Answers 6

Comments

Comments

Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

6 Answers 6

Comments

Comments

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related