c# - Showing Javascript from CodeBehind Page NOT Working! -

i want show javascript when user submit page. calling javascript through code behind (i think easy). here code:

 messagebox1("testing message"); //calling function!   private void messagebox1(string msg) //this in code behind of page.     {           // cleans message allow single quotation marks         string cleanmessage = msg.replace("'", "\\'");         string script = "<script type=\"text/javascript\">alert('" + cleanmessage + "');</script>";          // gets executing web page         page page = httpcontext.current.currenthandler page;          // checks if handler page , script isn't allready on page         if (page != null && !page.clientscript.isclientscriptblockregistered("alert"))         {             page.clientscript.registerclientscriptblock(typeof(commsetup), "alert", script);         }       } 

this not working...what doing wrong here? thank you!

use static method pop alert:

  public static void js_alert(string message)     {         // cleans message allow single quotation marks         string cleanmessage = message.replace("'", "\\'");         string script = "<script type=\"text/javascript\">alert('" + cleanmessage + "');</script>";          // gets executing web page         page page = httpcontext.current.currenthandler page;          // checks if handler page , script isn't allready on page         if (page != null && !page.clientscript.isclientscriptblockregistered("alert"))         {             page.clientscript.registerclientscriptblock(typeof(utilities), "alert", script);         }     } 

edit: "utilities" should name of class place method in. mine happens called utilities. if putting in code-behind partial class, called whatever web page called .cs on end.