用javascript按需加载.js和.css文件

项目需要在JS中动态加载JS文件，正好搜到一篇文章，先放这，然后去测一下：
<script language=javascript>
2
3 function JSandCSSRegistration()
4 {
5 document.createStyleSheet("style.css");
6 var head = document.getElementsByTagName('HEAD').item(0);
7 var script = document.createElement('SCRIPT');
8 script.src = "common.js";
9 script.type = "text/javascript";
10 head.appendChild(script);
11 }
12
13 JSandCSSRegistration();
14 </script>

来源：http://www.cnblogs.com/bestcomy/archive/2005/11/05/263191.html