请问为什么非得用 this 而不可以用aLi[i]呢？

Question

window.onload=function () {
   var aLi=document.getElementsByTagName('a');
   for (var i=0; i<aLi.length; i++) {
       aLi[i].onclick=function () {
           this.parentNode.style.display='none';
       }
   }
}

Answer 1

同步执行, 循环不会等待你的点击所触发的函数的执行,当你点击的时候,全局变量i已经经过循环变为了length

Answer 2

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