JavaScript闭包el.addEventListener不是一个函数

Question

<div id="a">ONE</div>
<div id="b">TWO</div>
<div id="c">THREE</div>
var el = document.getElementsByTagName("div");

for ( var i = 0; i < el.length; i++ ) (function(){
 el.addEventListener("click",function(){
  console.log(this.id + " " + this.innerHTML);
 },false);
})(i);

Gives me error "el.addEventListener is not a function", what is the problem?

Answer 1

el是一个HTMLCollection ，你忘了使用索引：

el[i].addEventListener("click",function(){...};

Answer 2

You're missing [i] (index) in your code (it must be el[i] ), thought addEventListener doesn't work in IE versions. To fix this problem you can do something like this:

function evt(elem,type,fn) { // element, event type, function
    if ( elem.addEventListener ) {
        elem.addEventListener(type,fn,false);
    } else {
        elem.attachEvent("on" + fn);
    }
}