文件 Ajax.html 向 服务器文件 users.xml 发送数据请求Ajax.html 如下:<html><script>
function createAjax(){
var Ajax=false;
if(window.XMLHttpRequest){
//非IE系列,符合W3C标准,或者是IE7,IE8
Ajax=new window.XMLHttpRequest();
if(Ajax.overrideMimeType){
Ajax.overrideMimeType("text/xml");
}
}else if(window.ActiveXObject){
//IE系列的低版本
var version=['Microsoft.XMLHTTP','MSXML.XMLHTTP','Msxml2.XMLHTTP.7.0','Msxml2.XMLHTTP.6.0','Msxml2.XMLHTTP.5.0','Msxml2.XMLHTTP.4.0','Msxml2.XMLHTTP.3.0','Msxml2.XMLHTTP'];
for(var i=0;i<version.length;i++){
try{
Ajax=new ActiveXObject(version[i]);
if(Ajax){
return Ajax;
}
}
catch(e){
Ajax=false;
}
}
}
return Ajax;
}
var Ajax=null;
function show(){
Ajax=createAjax();
Ajax.onreadystatechange=function(){
if(Ajax.readyState==4){
if(Ajax.status==200){
var dom=Ajax.responseXML;
var users=dom.getElementsByTagName("user");
alert(users.length); //问题:为什么返回的长度是 0
}else{
alert("页面请求失败");
}
}
}
Ajax.setRequestHeader("Content-Type","application/x-www-form-urlencoded")
Ajax.send("name=tianxiaokang&age=22");
}
</script>
<input type="button" onclick="show()" value="请求">
</html>users.xml 文件如下:
<?xml version="1.0" ?>
<users>
<user>
<name>zhangsan</name>
<age>22<age>
</user>
<user>
<name>zhangsan</name>
<age>22<age>
</user>
<user>
<name>zhangsan</name>
<age>22<age>
</user>
</users>
function createAjax(){
var Ajax=false;
if(window.XMLHttpRequest){
//非IE系列,符合W3C标准,或者是IE7,IE8
Ajax=new window.XMLHttpRequest();
if(Ajax.overrideMimeType){
Ajax.overrideMimeType("text/xml");
}
}else if(window.ActiveXObject){
//IE系列的低版本
var version=['Microsoft.XMLHTTP','MSXML.XMLHTTP','Msxml2.XMLHTTP.7.0','Msxml2.XMLHTTP.6.0','Msxml2.XMLHTTP.5.0','Msxml2.XMLHTTP.4.0','Msxml2.XMLHTTP.3.0','Msxml2.XMLHTTP'];
for(var i=0;i<version.length;i++){
try{
Ajax=new ActiveXObject(version[i]);
if(Ajax){
return Ajax;
}
}
catch(e){
Ajax=false;
}
}
}
return Ajax;
}
var Ajax=null;
function show(){
Ajax=createAjax();
Ajax.onreadystatechange=function(){
if(Ajax.readyState==4){
if(Ajax.status==200){
var dom=Ajax.responseXML;
var users=dom.getElementsByTagName("user");
alert(users.length); //问题:为什么返回的长度是 0
}else{
alert("页面请求失败");
}
}
}
Ajax.setRequestHeader("Content-Type","application/x-www-form-urlencoded")
Ajax.send("name=tianxiaokang&age=22");
}
</script>
<input type="button" onclick="show()" value="请求">
</html>users.xml 文件如下:
<?xml version="1.0" ?>
<users>
<user>
<name>zhangsan</name>
<age>22<age>
</user>
<user>
<name>zhangsan</name>
<age>22<age>
</user>
<user>
<name>zhangsan</name>
<age>22<age>
</user>
</users>
alert(dom); 弹出什么。
url = "send.php?cleanTmp=clean&ran="+Math.random();
method = "GET";
xmlHttp.open(method,url,true);
xmlHttp.onreadystatechange = show;
xmlHttp.send(null);
function show(){……}
<users>
<user>
<name>zhangsan</name>
<age>22</age>
</user>
<user>
<name>zhangsan</name>
<age>22</age>
</user>
<user>
<name>zhangsan</name>
<age>22</age>
</user>
</users>
改成json吧。xml多费劲