php Ajax 局部刷新:
HTML部分
</head>
<body>
<h1>Ajax动态显示时间</h1>
<input type="button" value="开始显示时间" id="go" onclick="start()" />
<p>当前时间：<font color="red"><span id="showtime"></span></font></p>
</body>
<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>
PHP部分
<?php
header("cache-control:no-cache,must-revalidate");
header("Content-Type:text/html;charset=utf-8");
$time = "2012-1-20 18:00:00";
$dt_element=explode(" ",$time);
$date_element=explode("-",$dt_element[0]);
$time_element=explode(":",$dt_element[1]);
$date = mktime($time_element[0],$time_element[1],$time_element[2],$date_element[1],$date_element[2],$date_element[0]);
$nowTime = time();
$showtime = date("北京时间Y年m月d日H:i:s",$date-$nowTime);
if($showtime<="北京时间1970年01月01日08:00:00"){
echo "happy new year";
}
echo $showtime;