<!DOCTYPE html>
<html lang="zh-cn">
<head>
<meta charset="UTF-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>放大镜</title>
<style>
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
.box {
position: relative;
top: 50px;
left: 50px;
width: 240px;
height: 440px;
background-color: #ccc;
padding: 20px;
}
.box > img {
width: 200px;
height: 400px;
}
.box .mask {
position: absolute;
top: 0;
left: 0;
width: 100px;
height: 100px;
background-color: yellow;
opacity: 0.5;
display: none;
cursor: move;
}
.box .big {
position: absolute;
top: 0;
left: 300px;
width: 400px;
height: 800px;
display: none;
overflow: hidden;
}
.box .big img {
position: absolute;
top: 0;
left: 0;
}
</style>
</head>
<body>
<div class="box">
<img src="../images/big.jpg" alt="" />
<div class="mask"></div>
<div class="big">
<img src="../images/big.jpg" alt="" />
</div>
</div>
</body>
<script>
let box = document.querySelector(".box");
let mask = document.querySelector(".mask");
let big = document.querySelector(".big");
let bigImg = big.querySelector("img");
//给盒子绑定移入移出事件
box.addEventListener("mouseover", function () {
mask.style.display = "block";
big.style.display = "block";
});
box.addEventListener("mouseout", function () {
mask.style.display = "none";
big.style.display = "none";
});
//绑定盒子内移动事件
box.addEventListener("mousemove", function (e) {
//获取鼠标在盒子内的坐标
let x = e.pageX - this.offsetLeft;
let y = e.pageY - this.offsetTop;
//减去遮罩层自身一半的宽高,让鼠标始终在遮罩层中央
let maskX = x - mask.offsetWidth / 2;
let maskY = y - mask.offsetHeight / 2;
//遮罩层最大移动距离
let maskMoveX = box.offsetWidth - mask.offsetWidth;
let maskMoveY = box.offsetHeight - mask.offsetHeight;
//大图片最大移动距离
let bigImgMoveX = bigImg.offsetWidth - big.offsetWidth;
let bigImgMoveY = bigImg.offsetHeight - big.offsetHeight;
//限制遮罩层不超出盒子
if (maskX <= 0) {
maskX = 0;
} else if (maskX >= maskMoveX) {
maskX = maskMoveX;
}
if (maskY <= 0) {
maskY = 0;
} else if (maskY >= maskMoveY) {
maskY = maskMoveY;
}
mask.style.left = maskX + "px";
mask.style.top = maskY + "px";
//大图片移动距离 = -(遮罩层移动距离 * 大图片最大移动距离 / 遮罩层的最大移动距离)
bigImg.style.left = -((maskX * bigImgMoveX) / maskMoveX) + "px";
bigImg.style.top = -((maskY * bigImgMoveY) / maskMoveY) + "px";
});
</script>
</html>
放大镜特效——Javascript
于 2022-04-03 11:03:40 首次发布