JS通过ajax动态读取xml文件内容的方法

<!DOCTYPE html>
<html>
<head>
<script>
function loadXMLDoc(url)
{
var xmlhttp;
if (window.XMLHttpRequest)
 {// code for IE7+, Firefox, Chrome, Opera, Safari
 xmlhttp=new XMLHttpRequest();
 }
else
 {// code for IE6, IE5
 xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
 }
xmlhttp.onreadystatechange=function()
 {
 if (xmlhttp.readyState==4 && xmlhttp.status==200)
  {
  document.getElementById('A1').innerHTML=xmlhttp.status;
  document.getElementById('A2').innerHTML=xmlhttp.statusText;
  document.getElementById('A3').innerHTML=xmlhttp.responseText;
  }
 }
xmlhttp.open("GET",url,true);
xmlhttp.send();
}
</script>
</head>
<body>
<h2>Retrieve data from XML file</h2>
<p><b>Status:</b><span id="A1"></span></p>
<p><b>Status text:</b><span id="A2"></span></p>
<p><b>Response:</b><span id="A3"></span></p>
<button onclick="loadXMLDoc('note.xml')">Get XML data</button>
</body>
</html>

<note>
<to>Tove</to>
<from>Jani</from>
<heading>Reminder</heading>
<body>Don't forget me this weekend!</body>
</note>