//前臺的請求頁面
<script type="text/javascript">
<!--
var xmlHttp;
function createXMLHttpRequest(){
if(window.ActiveXObject){
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
else if(window.XMLHttpRequest){
xmlHttp = new XMLHttpRequest();
}
}
function start(){
createXMLHttpRequest();
var url="getTime.php";
xmlHttp.open("GET",url,true);
xmlHttp.onreadystatechange = callback;
xmlHttp.send(null);
}
function callback(){
if(xmlHttp.readyState == 4){
if(xmlHttp.status == 200){
document.getElementById("showtime").innerHTML = xmlHttp.responseText;
setTimeout("start()",1000);
}
}
}
</script>
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=utf-8" />
</head>
<body>
<h1>Ajax動態顯示時間</h1>
<input type="button" value="開始顯示時間" id="go" onclick="start()" />
<p>當前時間：<font color="red"><span id="showtime"></span></font></p>
</body>
</html>//後臺頁面的請求
<?php
header("cache-control:no-cache,must-revalidate");
header("Content-Type:text/html;charset=utf-8");
date_default_timezone_set('PRC');
$showTime = date('Y-m-d H:i:s');
echo $showTime;
?>