利用JS实现购物网站商品放大镜效果

大家几乎都有在网上购物的经验，有的网站会有一个商品放大镜功能，

就是把鼠标移到图片上的时候，旁边会有另外一张大的图片展示，等同于

放大镜效果，那这样的效果怎样实现的呢，我把代码发给大家，请大家参考。

利用JS实现购物网站商品放大镜效果-LMLPHP

<!DOCTYPE html>

<html lang="en">

<head>

    <meta charset="UTF-8">

    <title>放大镜</title>

    <style>

    *{margin:0;padding: 0;}

    #warp{width: 1184px;height:500px;margin:50px auto 0;background-color: #ccc;overflow: hidden;padding: 10px;position: relative;}

    #warp #minbox{width: 350px;height: 350px;float: left;position: relative;}

    #maxbox{width: 400px;height: 400px;position: absolute;left: 380px;overflow: hidden;display: none;}

    #maxbox img{width: 800px;height: 800px;position: absolute;}

    #con{float: left;margin-left: 20px;}

    #meng{width: 175px;height: 175px;position: absolute;background-color:yellow;opacity:0.4;filter:alpha(opacity=40);left: 0;top: 0;display: none;}

    </style>

</head>

<body>

    <div id="warp">

        <div id="minbox">

            <img src="data:images/min.jpg" alt="">

            <p id="meng"></p>

        </div>

        <div id="maxbox">

            <img src="data:images/max.jpg" alt="">

        </div>

        <div id="con">

            <img src="data:images/msg.png" alt="">

        </div>

    </div>

    <script>

        var minbox=document.getElementById('minbox');

        var meng=document.getElementById('meng');

        var maxbox=document.getElementById('maxbox');

        var maximg=maxbox.getElementsByTagName('img')[0];

        var minimg=minbox.getElementsByTagName('img')[0];

        function offsetTL(obj){

            var ofL=0,ofT=0;

            while(obj){

                ofL+=obj.offsetLeft+obj.clientLeft;

                ofT+=obj.offsetTop+obj.clientTop;

                obj=obj.offsetParent;

            }

            return{left:ofL,top:ofT};

        }

        minbox.onmousemove=function(e){

            var e=e||window.event;

            meng.style.display='block';

            maxbox.style.display='block';

            var niubi1=e.clientX-offsetTL(minbox).left-meng.clientWidth/2;//蒙板的X坐标

            var niubi2=e.clientY-offsetTL(minbox).top-meng.clientHeight/2;//蒙板的Y坐标

            var bili=maximg.clientWidth/minimg.clientWidth;

            if (niubi1<=0) {

                niubi1=0;

            }else if (niubi1>=minbox.clientWidth-meng.clientWidth) {

                niubi1=minbox.clientWidth-meng.clientWidth;

            }

            if (niubi2<=0) {

                niubi2=0;

            }else if (niubi2>=minbox.clientHeight-meng.clientHeight) {

                niubi2=minbox.clientHeight-meng.clientHeight;

            }

            console.log(niubi1);

            console.log(niubi2);

            meng.style.left=niubi1+'px';

            meng.style.top=niubi2+'px';

            maximg.style.left=-parseInt(meng.style.left)*bili+'px';

            maximg.style.top=-parseInt(meng.style.top)*bili+'px';

        }

        minbox.onmouseout=function(){

            meng.style.display='none';

            maxbox.style.display='none';

        }

    </script>

</body>

</html>