Java Script to use XMLHttpRequest : readyState, statusText , responseText, responseXML

The below is a simple HTML code containing JAVA script to use the object XMLHttpRequest to retrieve the contents of a weburl when GET is applied. Simple to say do HTTP GET and show the contents of URL.

<html>
<head>
<script type="text/javascript">
function loadXMLDoc()
{
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function()
{
alert('Http State is:' + xmlhttp.readyState);
alert('HTTP Status is :' + xmlhttp.statusText);
if (xmlhttp.readyState==4 )
    {
    if ( xmlhttp.status==200 )
    {
       alert('Response data as String :' + xmlhttp.responseText);
       alert('Response data as XML:' + xmlhttp.responseXML);
    }
    }
}
try {
      xmlhttp.open("GET","http://www.krishnababug.com/",true);
      xmlhttp.send("");
      }
      catch (e) {
                 alert(e);
                }
}

</script>
</head>
<body>

<h2>How to use XMLHttpRequest object</h2>
<div id="myDiv"></div>
<button type="button" onclick="loadXMLDoc()">Load URL - Click to change state</button>

</body>
</html>

References:
[1] [2]
Note : working only on Internet Explorer