日期:2014-05-16  浏览次数:20408 次

ajax的一个运用 XMLHttpRequest
script2.html文件代码如下:
JScript code
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Ajax Demonstration</title>
<style>
.displaybox {
    width:150px;
    background-color:#FFFFFF;
    border:2px solid #000000;
    padding:10px;
    font:24px "微软雅黑";
    margin:auto;
}
</style>
<script type="text/javascript">
function getXMLHTTPRequest() {
    try {
        req = new XMLHttpRequest();
    }
    catch(err1) {
        try {
            req = new ActiveXObject("Msxml2.XMLHTTP");
        }
        catch(err2) {
            try {
                req = new ActiveXObject("Microsoft.XMLHTTP");
            }
            catch(err3) {
                req = false;
            }
        }
    }
    return req;
}

var http = getXMLHTTPRequest();

function getServerTime() {
    var myurl = "telltimeXML.php";
    myRand = parseInt(Math.random() * 999999999999999);
    var modurl = myurl + "?rand=" + myRand;
    http.open("GET", modurl, true);
    http.onreadystatechange = useHttpResponse;
    http.send(null);
}

function useHttpResponse() {
    if (http.readyState == 4) {
        if (http.status == 200) {
            var timeValue = http.responseXML.getElementsByTagName('timenow')[0];
            document.getElementById('showtime').innerHTML = timeValue.childNodes[0].nodeValue;
        }
        else {
            document.getElementById('showtime').innerHTML = '<img src="anim.gif">';
        }
    }
}

</script>
</head>

<body style="background-color:#CCCCCC; text-align:center">
<h1>Ajax Demostration</h1>
<h2>Getting the server time without page refresh</h2>
<form>
<input type="button" value="Get Server Time"  />
</form>
<div id="showtime" class="displaybox"></div>
</body>
</html>


telltimeXML.php代码如下:
PHP code
<?php
date_default_timezone_set('PRC');
echo '<?xml version="1.0" encoding="utf-8" ?><clock1><timenow>'.date("H:i:s").'</timenow></clock1>';
?>


我想通过点击 Get Server Time获取时间,但是并没有实现此功能。谁帮我解答下。 还要请教大家像这种情况该如何调试?

------解决方案--------------------
Eclipse firebug 打断点联调
------解决方案--------------------
你把方法都定义好了可是没有看到你调用的地方啊。。 把那个按钮写成这个试试:
<input type="button" value="Get Server Time" onclick="getServerTime()" />
------解决方案--------------------
你要弄懂ajax的原理就行了