<html>
<head>
<script src="https://libs.baidu.com/jquery/1.10.2/jquery.min.js">
</script>
<script>
$(document).ready(function(){
$(document).ajaxError(function(e,xhr,opt){
alert("Error requesting " + opt.url + ": " + xhr.status + " " + xhr.statusText);
});
$("button").click(function(){
$("div").load("wrongfile.txt");
});
});
</script>
</head>
<body>
<div><h2>Let AJAX change this text</h2></div>
<button>Change Content</button>
</body>
</html>