caller.html
<html> <head> <script type="text/javascript"> function callJs(jsFileName) { var js = document.createElement('script'); js.src = jsFileName; try { document.getElementsByTagName('head')[0].appendChild(js); } catch (exp) {} js = null; } callJs("callee.js"); </script> </head> </html>
callee.js
alert("hello, i am callee.js");