<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title>Title</title>
<style>
* {
margin: 0;
padding: 0;
}
.box {
width: 350px;
height: 350px;
margin: 100px;
border: 1px solid #ccc;
position: relative;
}
.big {
width: 400px;
height: 400px;
position: absolute;
top: 0;
left: 360px;
border: 1px solid #ccc;
overflow: hidden;
display: none;
}
.mask {
width: 175px;
height: 175px;
background: rgba(255, 255, 0, 0.4);
position: absolute;
top: 0px;
left: 0px;
cursor: move;
display: none;
}
.small {
position: relative;
}
</style>
</head>
<body>
<div class="box" id="box">
<div class="small"><!--小层-->
<img src="images/small.png" width="350" alt=""/>
<div class="mask"></div><!--遮挡层-->
</div><!--小图-->
<div class="big"><!--大层-->
<img src="images/big.jpg" width="800" alt=""/><!--大图-->
</div><!--大图-->
</div>
<!--导入外部的js文件-->
<script src="common.js"></script>
<script>
var box = my$("box");
var small = box.children[0];
var big = box.children[1];
var mask = small.children[1];
var bigImage = big.children[0];
box.onmouseover = function () {
mask.style.display = "block";
big.style.display = "block";
};
box.onmouseout = function () {
mask.style.display = "none";
big.style.display = "none";
};
small.onmousemove = function (e) {
var x = e.clientX - mask.offsetWidth / 2;
var y = e.clientY - mask.offsetHeight / 2;
x = x - 100;
y = y - 100;
x = (x < 0)? 0:x;
y = (y < 0)?0:y;
x = (x > small.offsetWidth - mask.offsetWidth)? small.offsetWidth - mask.offsetWidth: x;
y = (y > small.offsetHeight - mask.offsetHeight)? small.offsetHeight - mask.offsetHeight: y;
mask.style.left = x + "px";
mask.style.top = y + "px";
var ratio = (bigImage.offsetWidth - big.offsetWidth) / (small.offsetWidth - mask.offsetWidth);
var moveX = parseInt(x * ratio);
var moveY = parseInt(y * ratio);
bigImage.style.marginLeft = -moveX + "px";
bigImage.style.marginTop = -moveY + "px";
};
</script>
</body>
</html>