How to popup page from cs file in DotNet

I display the success msg in the same aspx page from cs file......
How to display the same using popup page..Also tell me how to transfer values from my page to that pop up page.....

const String approvedFormat = "<p>Transaction Successful!<br />Transaction ID: {0}<br />Transaction Completed at {1}<br />Customer name: {2}<br />Amount paid: {3}</p>";
            const String declinedMessage = "<p>Transaction Declined.<br />Please check your information and try again.<br />If you believe you have received this message in error,<br />please contact us at your local office.</p>";
            if (approved)
            {
                divSuccessMessage.InnerHtml = String.Format(approvedFormat, authCode, DateTime.Now.ToString(), txtFirstName.Text + " " + txtLastName.Text, txtPayment.Text);
                divSuccessMessage.Visible = true;
               
            }