源代码 ：
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<html><!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('p1').innerHTML="Last modified: " + xmlhttp.getResponseHeader('Last-Modified'); } } xmlhttp.open("GET",url,true); xmlhttp.send(); } </script> </head> <body> <p id="p1">The getResponseHeader() function is used to return specific header information from a resource, like length, server-type, content-type, last-modified, etc.</p> <button onclick="loadXMLDoc('/try/ajax/ajax_info.txt')">Get "Last-Modified" information</button> </body> </html>
运行结果