<script type="text/javascript" src="/js/jquery.js"></script>
<script type="text/javascript">
$(document).ready(function(){
$("div").ajaxSend(function(e,xhr,opt){
$(this).html("正在请求:" + opt.url);
$("button").click(function(){
$("div").load("/example/jq/demo_ajax_load.html");
<div id="txt"><h2>通过 AJAX 改变文本</h2></div>