'Sys' is undefined javascript error

Question

I am getting the following error:

Microsoft JScript runtime error: 'Sys' is undefined

While trying to execute:

<head id="Head1" runat="server">
    <title>Untitled Page</title>
    <script language="javascript" type="text/javascript">

        //ERROR IN THIS LINE!!!
        Sys.WebForms.PageRequestManager.getInstance().add_endRequest(onUpdated());


          function onUpdated() {
                // get the update progress div
                var pnlPopup = $get("div2"); 
                // make it invisible

            }

    </script>
</head>

Ensure your script is below the scriptmanager. Maybe try to put your script tag into body and see what happens — k0ni
– k0ni, Commented Oct 16, 2009 at 10:51

k0ni · Accepted Answer · 2009-10-16 11:08:27Z

6

Ensure you have a Scriptmanager on the page and the script is below the scriptmanager. Maybe try to put your script tag into body and see what happens.

I don't know how you can fix that that its not in the body, but maybe there is a callback from Sys when its loaded

You don't need brackets to tell which function is neeeded:

Sys.WebForms.PageRequestManager.getInstance().add_endRequest(onUpdated);

edited Oct 16, 2009 at 11:08

answered Oct 16, 2009 at 10:52

k0ni

2,4674 gold badges23 silver badges25 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

dani Over a year ago

I've added the JS below the scriptmanager and it worked! But I don't like the idea of having js in the body... Can something be done about that? Any way, update your answer(add what what you've posted in comment) and i will Accept it :)

tvanfosson · Accepted Answer · 2009-10-16 10:53:28Z

2

If that is your full code, then the problem is that the Microsoft AJAX libraries aren't being included. If it isn't your full code, then you need to post more as it's a little hard to get beyond the fact that the library isn't included. Somewhere in your file -- prior to the line you are having problems with you need to have a javascript include like:

<script type="text/javascript" src="/scripts/MicrosoftAjax.js" />

As well as probably a few others.

Note: I'm talking about the generated source. Showing more complete markup would probably also suffice.

answered Oct 16, 2009 at 10:53

tvanfosson

534k102 gold badges703 silver badges801 bronze badges

Comments

Grubl3r · Accepted Answer · 2009-12-02 10:06:06Z

0

I'm a bit late to the discussion here, but a simple solution is to create a "ASP.NET AJAX-Enabled Web Site" in Visual Studio and then merge the web.config from that site with your existing site.

In this way you get all the configuration you need without having to carefully read through a lot of docs. Speed is of the essence and all that :)

answered Dec 2, 2009 at 10:06

Grubl3r

4572 gold badges7 silver badges20 bronze badges

1 Comment

Greg Gum Over a year ago

This is what I found was missing from my web.config to resolve this error: <add key="UnobtrusiveJavaScriptEnabled" value="true" />

Hemant Kumar · Accepted Answer · 2013-10-30 11:51:36Z

0

You can fix this issue by setting the EnableCDN property to "true".refer this link

answered Oct 30, 2013 at 11:51

Hemant Kumar

4,6219 gold badges58 silver badges96 bronze badges

Comments

user7618071 · Accepted Answer · 2017-02-24 16:20:41Z

0

I had the same issue , after all findings I found that the required script files ("MicrosoftAjax.js", "WebForms.js","jquery", "bootstrap" etc..) were not loaded properly which was causing me 3 errors "Sys' is undefined", "webform_docallback is undefined" and "webform_initcallback' is undefined", my actual problem was I had reference to these files which where not included in my propject, my bad I have not noticed it, I have tried all the possible solutions from the internet before I really found that my js files were not included and thats the reason its not loaded properly.

Hope this helps..

answered Feb 24, 2017 at 16:20

user7618071

1

Collectives™ on Stack Overflow

'Sys' is undefined javascript error

5 Answers 5

1 Comment

Comments

1 Comment

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

5 Answers 5

1 Comment

Comments

1 Comment

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related