js - 02课 4 浅谈this -3

1.两种方式绑定, this 不同的指向

<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
    <style>
        li{width: 100px; height:150px;float:left; margin-right:30px; background: #f1f1f1;position: relative; z-index: 1;}
        div{width: 80px; height:200px; background:red; position: absolute; top:75px;left:10px;display: none}
    </style>
</head>
<body>
<ul>
    <li>
        <div></div>
    </li>
    <li>
        <div></div>
    </li>
    <li>
        <div></div>
    </li>
</ul>
<script>
    window.onload = function(){
        var aLi = document.getElementsByTagName('li')
        for(var i = 0; i < aLi.length; i++){
            aLi[i].onmouseover = function(){
                var _this = this;
                showDiv(_this);
            }
            aLi[i].onmouseout = hideDiv;
        }
    }
    function showDiv(_this){
        _this.getElementsByTagName('div')[0].style.display = 'block';
    }
    function hideDiv(){
        this.getElementsByTagName('div')[0].style.display = 'none';
    }
</script>
</body>
</html>

　　

posted @ 2016-10-19 23:36  黑土白云  阅读(134)  评论(0)    收藏  举报