Expression has been evaluated and has no value

Question

0.00/5 (No votes)

See more:

C#

protected void lbkSelect_Click(object sender, EventArgs e)
{
  LinkButton btndetails = sender as LinkButton;

  GridViewRow gvrow = (GridViewRow)btndetails.NamingContainer;

  txtID.Text = GridView1.DataKeys[gvrow.RowIndex].Value.ToString();
  lblAirlineName.Text = gvrow.Cells[0].Text;
  lblDeparture.Text = gvrow.Cells[1].Text;
  lblArrival.Text = gvrow.Cells[2].Text;
  lblDuration.Text = gvrow.Cells[3].Text;
  lblStops.Text = gvrow.Cells[4].Text;
  Label labelPrice = (Label)gvrow.Cells[5].FindControl("Label1");

  lblPrice.Text = labelPrice.Text;

  this.ctlModalPopupExtender.Show();
}

On applying watch to this.ctlModalPopupExtender.Show(); it shows me:
expression has been evaluated and has no value. And it does not display value on popup.

[Edit/ Code Block Added by Jibesh /Edit]

Posted 8-Jan-13 20:31pm

Arpit Garg1

Updated 8-Jan-13 20:35pm

Jibesh

v2

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Christian Graus · Accepted Answer · 2013-01-08T21:19:00

"expression has been evaluated and has no value." means the debugger ran the expression and it didn't return any thing. It means the Show method has no return value, but the debugger ran it.

What is a modalpopupextender ? Is it part of the AJAX library ? You're doing a postback, so you're not using AJAX ( unless the AJAX library is doing it ) ? If you're doing an AJAX postback, why do you want to ask an AJAX control to show itself as well ?

I don't use the ASP.NET AJAX library ( it's horrendous ) but this article ModalPopupExtender from Server Side Code[^] seems to indicate that what you're doing is right. The control will, of course, not show when you call the method in the debugger, the method would just tell the control to show itself when the page is rendered. You know that, right ?