displaying a messagebox.

[Gopal Sharma akki]

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
 
public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
 
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        if ((TextBox1.Text == "gopal") && (TextBox2.Text == "smile"))
        {
            Response.Redirect("Default2.aspx");
        }
        else
        {
            MessageBox.Show("Invalid Username and Password combination");
        }
    }
}

this messagebox gives an error that messagebox does not found in current context.

[Plater]

Be sure to add the namespace reference to classes you use:
using System.Windows.Forms;

EDIT: Oops this is a webpage? That messagebox will popup on the server, not on the client.
Backend code is only executed on the server.

You would need to use the javascript alert() function to popup a message on the client

[Gopal Sharma akki]

i m using VBScript as a scripting language.
after using namespace System.Windows.Forms; it gives an error that the namespace name 'Windows' does not exists in the namespace 'System'(are you missing an assembly refrence?).

[mzmishra]

try something like this

string script =" MsgBox 'Invalid Username and Password combination'";
Page.RegisterStartupScript("message", "<script language=\"VBScript\">" + script + "</script>");