title: The name 'MessageBox' does not exist in the current context
body: <pre><code>if (Session["Customer_ID"] == null)
  {
       if (MessageBox.Show("Do you want to login or countinue without login?", "Confirm", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes)
        {
            // user clicked yes redirects to login page
        }
        else
        {
            // user clicked no do something
        }
  }         
  </code></pre>
  
  <p>it shows the "The name 'MessageBox' does not exist in the current context" error 
  i have used System.Windows.Forms</p>