Running a Client Side Script from Server Side Code in ASP.NET

Paul S. Chapman

4.00/5 (1 vote)

Jan 18, 2013

CPOL

31532

How to run a client side script from server side code in ASP.NET

I needed to get a pop-up window to come up in ASP.NET. Now while JavaScript happily does this (with the alert(); function, ASP.NET does not. So I needed to work out how to do it. Another wrinkle in this comes from Ajax. None of the JavaScript code seemed to work when placed in an AJAX page.

As I have now been tasked with changing this code and moving from the Anthem Ajax library to a pure MS solution, it was time for this died in the wool VB/C# developer to get his head around getting these scripts working.

To do this:

Create a simple ASP.NET Web Project
Right click with the mouse on the Project title (this will be bold)

Select ‘Add’ and then ‘New Item’

<%@ Page Language="C#" AutoEventWireup="true" 
CodeBehind="TestPage.aspx.cs" Inherits="TrustTest.TestPage" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title></title>
    <script type="text/javascript">
    
      function pageLoad() {
      }
    
    </script>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:ScriptManager ID="ScriptManager1" runat="server">
            <Scripts>
                
            </Scripts>
        </asp:ScriptManager>
    </div>
    <asp:UpdatePanel ID="UpdatePanel1" runat="server">
        <ContentTemplate>
            <asp:Button ID="Button1" runat="server" Text="Press Me!" 
                onclick="Button1_Click" />
        </ContentTemplate>
    </asp:UpdatePanel>
    </form>
</body>
</html>

protected void Button1_Click(object sender, EventArgs e)
{
    ScriptManager.RegisterClientScriptBlock(this, typeof(Page), 
          "alertScript", "alert('you pressed me!');", true);
}

Select ‘AJAX Web Form’
Add a Button to the page
Now add a 'click' event handler to the button
And there it is. Now whenever you click on the button, a pop up appears saying ‘you pressed me!’