Introduction Quite Often, We may wish to inform the user of a successful or an unsuccessful operation in a web form application. An effective way to communicate an important message to the user is through the use a MessageBox or a JavaScript "alert". The MessageBox class in the System.Windows.Forms namespace is usable only from Windows Forms and NOT ASP.NET Web Forms. In order to alert the user we need to add some client side code into the HTML page. This is a simple task but can become quite annoying if this functionality is required on a regular basis. Background Hence, It would be nice if we could simply call a static method from any page that would deal with the client side JavaScript required to display the alert's. This reusable asset explains about a small MessageBox class with a static Show(); method. This Class can be included in the Project and can be used by simply calling the Show method for displaying a Message Box. The code Code: ASP.NET Code: using System; using System.Collections; using System.ComponentModel; using System.Data; using System.Data.OleDb; using System.Drawing; using System.Web; using System.Web.SessionState; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.HtmlControls; using System.Text; namespace Message { /// <summary> /// Summary description for MessageBox. /// </summary> public class MessageBox { private static Hashtable m_executingPages = new Hashtable(); public MessageBox() { // // TODO: Add constructor logic here // } public static void Show( string sMessage ) { // If this is the first time a page has called this method then if( !m_executingPages.Contains( HttpContext.Current.Handler ) ) { // Attempt to cast HttpHandler as a Page. Page executingPage = HttpContext.Current.Handler as Page; if( executingPage != null ) { // Create a Queue to hold one or more messages. Queue messageQueue = new Queue(); // Add our message to the Queue messageQueue.Enqueue( sMessage ); // Add our message queue to the hash table. Use our page reference // (IHttpHandler) as the key. m_executingPages.Add( HttpContext.Current.Handler, messageQueue ); // Wire up Unload event so that we can inject // some JavaScript for the alerts. executingPage.Unload += new EventHandler( ExecutingPage_Unload ); } } else { // If were here then the method has allready been // called from the executing Page. // We have allready created a message queue and stored a // reference to it in our hastable. Queue queue = (Queue) m_executingPages[ HttpContext.Current.Handler ]; // Add our message to the Queue queue.Enqueue( sMessage ); } } // Our page has finished rendering so lets output the // JavaScript to produce the alert's private static void ExecutingPage_Unload(object sender, EventArgs e) { // Get our message queue from the hashtable Queue queue = (Queue) m_executingPages[ HttpContext.Current.Handler ]; if( queue != null ) { StringBuilder sb = new StringBuilder(); // How many messages have been registered? int iMsgCount = queue.Count; // Use StringBuilder to build up our client slide JavaScript. sb.Append( "<script language='javascript'>" ); // Loop round registered messages string sMsg; while( iMsgCount-- > 0 ) { sMsg = (string) queue.Dequeue(); sMsg = sMsg.Replace( "\n", "\\n" ); sMsg = sMsg.Replace( "\"", "'" ); sb.Append( @"alert( """ + sMsg + @""" );" ); } // Close our JS sb.Append( @"</script>" ); // Were done, so remove our page reference from the hashtable m_executingPages.Remove( HttpContext.Current.Handler ); // Write the JavaScript to the end of the response stream. HttpContext.Current.Response.Write( sb.ToString() ); } } } } Thanks
[FONT="]Hi, Thanks for allowing me to be a part of this forum. I look forward to becoming an active member. Jim [/FONT]
Hi everybody, I uploaded one file. But It can not display. I used internet explorer 8.0. How can I repair? Or some problems happened to IE8? Rgs
my name sijo and could you please help me for studying asp.net 2005 and i need your help please.Thank you
It is not my forum but forum is always of members and I am just a facilitator to keep things organized.