<html>
<head>
<script src="https://libs.baidu.com/jquery/1.10.2/jquery.min.js">
</script>
<script>
function changeSize()
{
$(this).animate({fontSize:"+=3px"});
}
function changeSpacing()
{
$(this).animate({letterSpacing:"+=2px"});
}
$(document).ready(function(){
$("body").delegate("p","click",changeSize);
$("body").delegate("p","click",changeSpacing);
$("button").click(function(){
$("body").undelegate("p","click");
});
});
</script>
</head>
<body>
<p>This is a paragraph.</p>
<p>This is another paragraph.</p>
<p>Click any p element to increase size and letterspacing.</p>
<button>Remove all "click" event handlers (added with the delegate() method) for all p elements</button>
</body>
</html>