<script language= "javascript " for= "window " event= "onload ">

EVENT   event   设置或获取脚本编写用于的事件   
FOR   htmlFor   设置或获取绑定到事件脚本的对象。 

可以这样理解。 

<script   language= "javascript "   for= "window "   event= "onload "> 
相当于 
<script   language= "javascript "> 
//   绑定 
window.attachEvent( "onload ",function()   { 
//   TODO 
}) 
</script>