I'm trying to write the server side script in PHP. The following code is supposed to show the value returned by time() inside a text box. But it is not doing that. Where is the problem?

Client Side Ajax Script:
Code:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head>
	<title>Ajax Practice</title>
	<script type="text/javascript">
	function GetXmlHttpObject() {
		var xmlHttp;
		try {
			// Firefox, Opera 8.0+, Safari
			xmlHttp=new XMLHttpRequest();
		}
		catch (e) {
			// Internet Explorer
			try {
				xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
			}
			catch (e)
			{
				try {
					xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
				}
				catch (e)
				{
					alert("Your browser does not support AJAX!");
					return false;
				}
			}
		}
		return xmlHttp;
	}

	function ajaxFunction() {
		var xmlHttp = GetXmlHttpObject();

		xmlHttp.onreadystatechange = function() {
			if (xmlHttp.readyState == 4) {// The request is complete
				document.myForm.time.value = xmlHttp.responseText;
			}
		}

		xmlHttp.open("GET", "http://localhost/time.php", true);
		xmlHttp.send(null);
	}
	</script>
</head>

<body>

<form name="myForm">
	Name: <input type="text" onkeyup="ajaxFunction();" name="username" />
	Time: <input type="text" name="time" />
</form>

</body>
</html>
Server Side PHP Script:
Code:
<?php
	print time();
?>
I'm using XAMPP and the file time.php is placed in C:\Program Files\XAMPP\xampp\htdocs. When I open http://localhost/time.php, it is showing correct result.

Please help.