最近遇到一个document.write("<script type='text/javascript' src='test.js'></script>")在ie浏览器不生效的问题，可用document.createElement("script");解决

  var s = document.createElement("script");
  s.type = "text/javascript";
  s.src = "test.js";
  document.getElementsByTagName("head")[0].appendChild(s);

不过document.write方式正确的写法应该如下：
document.write("<script type='text/javascript' src='test.js'><\/script>")