Como ya sabrán en Asp.net no contamos con el Control MessageBox , como en WinForms, el siguiente código muestra como crear el control y utilizarlo.

El código es el siguiente:

using System;

using System.Data.SqlClient;

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;

using System.Text;

public partial class _Default : System.Web.UI.Page

{

    protected void Page_Load(object sender, EventArgs e)

    {

        MessageBox.Show("Hola");

    }

    public class MessageBox

    {

        private static Hashtable m_executingPages = new Hashtable();

        private MessageBox() { }

        public static void Show(string sMessage)

        {

            if (!m_executingPages.Contains(HttpContext.Current.Handler))

            {

                Page executingPage = HttpContext.Current.Handler as Page;

                if (executingPage != null)

                {

                    Queue messageQueue = new Queue();

                    messageQueue.Enqueue(sMessage);

                    m_executingPages.Add(HttpContext.Current.Handler, messageQueue);

                    executingPage.Unload += new EventHandler(ExecutingPage_Unload);

                }

            }

            else

            {

                Queue queue = (Queue)m_executingPages[HttpContext.Current.Handler];

                queue.Enqueue(sMessage);

            }

        }

        private static void ExecutingPage_Unload(object sender, EventArgs e)

        {

            Queue queue = (Queue)m_executingPages[HttpContext.Current.Handler];

            if (queue != null)

            {

                StringBuilder sb = new StringBuilder();

                int iMsgCount = queue.Count;

                sb.Append("<script language='javascript'>");

                string sMsg;

                while (iMsgCount-- > 0)

                {

                    sMsg = (string)queue.Dequeue();

                    sMsg = sMsg.Replace("\n", "\\n");

                    sMsg = sMsg.Replace("\"", "'");

                    //sb.Append(@"alert( """ + sMsg + @""" );");

                    sb.Append(@"confirm( """ + sMsg + @""" );");

                }

                sb.Append(@"</script>");

                m_executingPages.Remove(HttpContext.Current.Handler);

                HttpContext.Current.Response.Write(sb.ToString());

            }

        }

    }

}

BY: IAN

Gracias A Gusi por hacernos llegar el codigo y postearlo

Atte: VicoNet