<html>
<body>
<p id="demo">Click the button to see if the specified namespace is default</p>
<button onclick="myFunction()">Try it</button>
<script>
function myFunction()
{
var d=document.documentElement;
var x=document.getElementById("demo");
x.innerHTML=d.isDefaultNamespace("http://www.w3.org/1999/xhtml");
}
</script>
<p><strong>Note:</strong> Internet Explorer 8 and earlier does not support the isDefaultNamespace method.</p>
</body>
</html>