<script language="javascript">
var script = document.createElement("script");
script.language = "javascript";
script.text = "alert(‘hello world!‘)";
document.body.appendChild(script);
</script>
另一方法：
http://blog.csdn.net/renfufei/article/details/18039237
如何动态在文档中加入＜script＞＜/script＞写入大段js
原文：http://www.cnblogs.com/webqiand/p/4195721.html