<html><head><script src="https://libs.baidu.com/jquery/2.1.4/jquery.min.js"></script><script>$(document).ready(function(){ $("p").one("click dblclick", function(){ $(this).animate({fontSize: "+=6px"}); });});</script></head><body><p>This is a paragraph.</p><p>This is another paragraph.</p><p>Click and double click any p element to increase its text size. Event handlers will trigger once per element per event type (one click, and one dblclick).</p></body></html>