Error: Operator '!' cannot be applied to operand of type object

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I have a error that shows: Operator '!' cannot be applied to operand of type object in my following code. How do i solve it?

C#

if (!(Session["counter"]))
        {
            counter = (int)Session["counter"];
        }

Posted 24-Jul-12 6:33am

kellycx

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3 solutions

Solution 3

As MSDN[^] states:

The logical negation operator (!) is a unary operator that negates its operand. It is defined for bool and returns true if and only if its operand is false.

hence you cannot apply it to integer variables.

You might change it to:

C#

if ( Session["counter"] != 0)
{
//...
}

Posted 24-Jul-12 6:42am

CPallini

Comments

kellycx 24-Jul-12 12:54pm

I changed the codes to the one you suggested but it still return me the same error. Is it because i declared it in my Page Load already?

This is my .cs code for Page Load:

protected void Page_Load(object sender, EventArgs e)
{
if (!(Page.IsPostBack))
{
Session["counter"] = null;
}
}

Sergey Alexandrovich Kryukov 24-Jul-12 14:30pm

No!! Read the answer by CPallini again. Can you read?
--SA

Sergey Alexandrovich Kryukov 24-Jul-12 14:30pm

Sure, a 5.
--SA

CPallini 24-Jul-12 15:58pm

Thank you very much Sergey Alexandr... Well, SA!
:-)

kellycx 25-Jul-12 3:12am

I think you dun understand what i am saying. It's OK i solved it myself already

CPallini 25-Jul-12 3:31am

If you are happy with that, well, I am happy too.

Solution 1

It depends on the value of the session variable Counter.

If you are assuming it is a integer value, you should be writing code like

if (!(int)Session["counter"] == 0)
{
  counter = ....
}

Posted 24-Jul-12 6:40am

Abhinav S

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Santhosh Kumar Jayaraman · Accepted Answer · 2012-07-24T15:24:00

Solution 4

Try this.

C#

(! (Session["Counter"] is null)
counter = (int)Session["counter"];

Posted 24-Jul-12 15:24pm

Santhosh Kumar Jayaraman