c# - JavaScript: Alert.Show(message) From ASP.NET Code-behind -

i reading javascript: alert.show(message) asp.net code-behind

i trying implement same. created static class this:

using system; using system.collections.generic; using system.linq; using system.web; using system.data; using system.data.sqlclient; using system.web; using system.text; using system.web.ui;  namespace registration.dataaccess {     public static class repository     {         /// <summary>          /// shows client-side javascript alert in browser.          /// </summary>          /// <param name="message">the message appear in alert.</param>          public static void show(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(alert), "alert", script);                 }              }      } } 

on line:

string script = "<script type="text/javascript">alert('" + cleanmessage + "');</script>";  

it showing me err: ; expected

and on

page.clientscript.registerclientscriptblock(typeof(alert), "alert", script);  

err: the type or namespace name 'alert' not found (are missing using directive or assembly reference?)

what doing wrong here?

here easy way:

response.write("<script>alert('hello');</script>");