Jon's Blog

.NET Development & More

Hiding ASP.NET Ajax Modal Popup Dialog Using JavaScript

Following is an easy way to hide the modal popup dialog extender from the AJAX control toolkit using JavaScript.  The key is to set a BehaviorID on the ModalPopupExtender.  Then you can use this ID to call the hide() method via Javascript like this:

function HideModal() {
  $find('modalPopupBehavior').hide();
}

In the full example below I am closing the modal popup dialog box when the user clicks on a link.

Full ASPX example:

<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="ajaxtk" %>

<!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>My Page</title>
    <link href="css/Test.css" rel="stylesheet" type="text/css" />
</head>
<body>
<form id="aspNetForm" runat="server">
    
<asp:ScriptManager ID="scriptMan" runat="server" />

<script type="text/javascript" language="javascript">
    function HideModal() {
        $find('modalPopupBehavior').hide();
    }
</script>

<asp:UpdatePanel ID="upnlMain" runat="server">
    <ContentTemplate>
    
        <div>
            <ajaxtk:ModalPopupExtender ID="modalPopup" runat="server" 
                BehaviorID="modalPopupBehavior"
                TargetControlID="btnPopup" PopupControlID="pnlPopup">
            </ajaxtk:ModalPopupExtender>
            
            <asp:Button ID="btnPopup" runat="server" Text="Show Popup" />
            
            <asp:Panel ID="pnlPopup" runat="server" CssClass="modalPopup" 
                style="width: 715px; display: none;">
                <div>
                    <p>
                    <a href="http://www.jonathanjungman.com/blog/" 
                        target="_blank" onclick="HideModal()">Hide Modal</a>
                    </p>
                </div>
            </asp:Panel>
        </div>
    
    </ContentTemplate>
</asp:UpdatePanel>
   
</form>
</body>
</html>

ASP.NET AJAX Control Toolkit: Bug with Modal Popup Extender

I found a bug in the September 30, 2009 release of the AJAX Control Toolkit.  When you press a button that is inside of a Modal Popup dialog box it will cause a full page postback instead of a partial postback.  When I reverted to the May 13, 2009 release this did not occur.

By the way, I also ran into another weird issue on the September 2009 release where random commas were being inserted into my text box on each postback.  If you are having this issue I also recommend reverting to the May 2009 release.