HTML anchor tag's onclick attribute does not call javascript function

Question

We have a DotNetNuke module running in an instance of DotNetNuke 5.4.4, installed on "Server A", a Windows Server 2008 R2 Standard machine with IIS 6.1 and Internet Explorer 11.

We're accessing our DotNetNuke module from "Server B", running Windows Server 2008 Standard, with Internet Explorer 9.

The issue happens when we click an anchor html element that has an onclick attribute, while accessing our module on Server B.

The anchor with the onclick is like:

<a onclick='OpenWindow("/DotNetNuke/DesktopModules/Module/View.aspx?dt=%c2%b2%c2");return false;' 
   href="http://000.00.0.0/DotNetNuke/DesktopModules/Module/View.aspx?dt=%c2%b2%c2"
   target='_blank'
   jQuery1431968126278="42">Doc name (SSN-SS-SSNN)</a>

And the OpenWindow function is like this

function OpenWindow(url) {
  window.open(url, '', 'top=15,scrollbars=yes,menubar=no,height=800,width=800,resizable=yes,toolbar=no,location=no,status=no');
}

As you can see we have an anchor element, with an onclick attribute, where it is supposed to call the OpenWindow javascript function, then return false, so the default action for clicking an anchor (browse to the href) does not happen.

When we click this link though (ONLY on server B), we get no popup window, no breakpoints in the OpenWindow function are hit, and the browser navigates to the href by opening a new tab (View.aspx). This suggests to me that the OpenWindow function referenced by the onclick attribute is not even running for some reason, even though it is on the anchor element, and works on any other server.

What I've tried

I compared the security settings, web.config files, and DotNetNuke settings between the Server A DotNetNuke and my local developer DotNetNuke instances, and found no differences in setup.

I compared the Server B Internet Explorer security settings to my security settings, and found no differences in setup.

On the advice of comments on this question, I tried changing the anchor tag to a span tag instead (removed href and target attributes), and I am seeing the same behavior. It works on Server A and Dev, but doesn't do anything on Server B now. I think the core issue is that either the onclick attribute is not being recognized, or is being blocked somehow.

I've now gone further and changed most of the <a>...</a> tags into <span>...</span> tags, with specific classes, that I then attach jQuery(...).live('click', ...) handlers to (using jQuery 1.4.2). That is allowing the clicks to work, but I still haven't resolved why the onclick attribute is being ignored.

What's weird..

If I open the developer tools (IE9), then click the "Edit" button to turn edit mode on and off again, all of the onclick attributes on anchor tags and img tags start working correctly, until I reload the page.

If I edit the onclick handler in any way manually through the developer tools, like say removing the return false; from the onclick handler, it will work, but if I put the return false; back to make it like I never changed anything, it stops working again.

What I'm trying to figure out

I am hitting a wall with what to check to figure out this issue. I can't reproduce it on my developer machine, and it works on Server A as well, so the code is working perfectly fine. I'm thinking there must be a setting that I am overlooking somewhere, but where? I have no idea what else to check at this point, and I'm looking for ideas.

Answer 1

I don't have an exact answer, but I can give you the general idea of what is happening and why.

The two servers are not getting identical content -- perhaps they are pointed at different CDNs, perhaps one has an old file of a JavaScript file somewhere -- you'll have to walk through them one by one.

Something, somewhere, is applying an onclick handler to all of your anchor tags.

At first I thought it was something attached to the body element and targeting your links, but I ruled that out. The fact you can edit the HTML and save it and then the link works means you are detaching whatever was attached to that link element.

I would:

• Save the entire web page from Site A
• Save the entire web page from Site B
• Run a diff tool against the two directories.