Detecting support for VML, help applying a previous post

Question

I found the following in a previous post but need some help with it:

// For VML detection, here's what google maps does (search for "function Xd"):

function supportsVml() { 
  if (typeof supportsVml.supported == "undefined") { 
    var a = document.body.appendChild(document.createElement('div')); 
    a.innerHTML = '<v:shape id="vml_flag1" adj="1" />'; 
    var b = a.firstChild; 
    b.style.behavior = "url(#default#VML)"; 
    supportsVml.supported = b ? typeof b.adj == "object": true; 
    a.parentNode.removeChild(a); 
  } 
  return supportsVml.supported;
} 

I would like to use the code to divert users to an alternative page when VML is not supported. Please could somebody show me how to write and implement the code to divert, say, to a page called alternative.html.

I have some knowledge of javascript but not this level!

Thanks.

Answer 1

You can just make a call to that function provided by Google, and it will return true if VML is supported and false if not. Don't forget, you will still need to add the xmlns for VML somewhere in your HTML.

if (!supportsVml())
    window.location = "http://somedomain.com/no-vml.html";

Also, I would recommend using a cross-browser library for drawing vector graphics. There's a few to choose from in this blog post: Canvas/SVG/VML Drawing Roundup.

Answer 2

VML is only supported in Internet Explorer (as of 5.0) and is not supported in any other browser. So checking for IE should be just enough. This can be done in many ways, for example: !!document.namespaces