JavaScript 在回调函数中闭包保存循环index

var elems = document.getElementsByTagName('a');

for (var i = 0; i < elems.length; i++) {

    (function (lockedInIndex) {

        elems[i].addEventListener('click', function (e) {
            e.preventDefault();
            alert('I am link #' + lockedInIndex);
        }, 'false');

    })(i);

}

　

var elems = document.getElementsByTagName('a');

for (var i = 0; i < elems.length; i++) {

    elems[i].addEventListener('click', (function (lockedInIndex) {
        return function (e) {
            e.preventDefault();
            alert('I am link #' + lockedInIndex);
        };
    })(i), 'false');

}

 var container = document.querySelector("body"), imgEle = null, length = 0, i = 0;

        length = this.imgList.length;
        for (; i < length; i++) {
            imgEle = this.imgList[i];
            imgEle.style.cursor = "pointer";
            imgEle.index = (function(num){
                alert(num);
                return num;
            })(i);
            imgEle.addEventListener("click", function(){
                CNLive.Pic.showFullPic(this);
                CNLive.Pic.controlBigPic();
            }, false);
        }