用Ajax读取Text格式的数据，只需要读取XMLHttpRequest对象返回的responseText属性即可。代码如下：
1、Client - helloworld.htm
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title>Ajax Hello World</title>
<script type="text/javascript">
var xmlHttp;
function createXMLHttpRequest(){
if(window.ActiveXObject){
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
else if(window.XMLHttpRequest){
xmlHttp = new XMLHttpRequest();
}
}
function startRequest(){
createXMLHttpRequest();
try{
xmlHttp.onreadystatechange = handleStateChange;
xmlHttp.open("GET", "data.txt", true);
xmlHttp.send(null);
}catch(exception){
alert("您要访问的资源不存在!");
}
}
function handleStateChange(){
if(xmlHttp.readyState == 4){
if (xmlHttp.status == 200 || xmlHttp.status == 0){
// 显示返回结果
alert("responseText's value: " + xmlHttp.responseText);
}
}
}
</script>
</head>
<body>
<div>
<input type="button" value="return ajax responseText's value"
onclick="startRequest();" />
</div>
</body>
</html>
2、Server - data.txt"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title>Ajax Hello World</title>
<script type="text/javascript">
var xmlHttp;
function createXMLHttpRequest(){
if(window.ActiveXObject){
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
else if(window.XMLHttpRequest){
xmlHttp = new XMLHttpRequest();
}
}
function startRequest(){
createXMLHttpRequest();
try{
xmlHttp.onreadystatechange = handleStateChange;
xmlHttp.open("GET", "data.txt", true);
xmlHttp.send(null);
}catch(exception){
alert("您要访问的资源不存在!");
}
}
function handleStateChange(){
if(xmlHttp.readyState == 4){
if (xmlHttp.status == 200 || xmlHttp.status == 0){
// 显示返回结果
alert("responseText's value: " + xmlHttp.responseText);
}
}
}
</script>
</head>
<body>
<div>
<input type="button" value="return ajax responseText's value"
onclick="startRequest();" />
</div>
</body>
</html>
hello world!
附源码：responseText.rar