@Author:Runsen
@Date:2020/6/1
作者介绍:Runsen目前大三下学期,专业化学工程与工艺,大学沉迷日语,Python, Java和一系列数据分析软件。导致翘课严重,专业排名中下。.在大学60%的时间,都在CSDN。
本文实现的Javascript实现放大镜效果,在这里Runsen带领大家来使用javaScript实现图片的放大和缩小。实现的效果图如下 。
素材下载:https://download.csdn.net/download/weixin_44510615/12484958
布局
一张相同的图片大的和小的,img1上有一个#list的div,通过鼠标移动list,根据list区域内的图片,来裁剪#small_box的div的图片,并将图片放大,显示出来。
js
完整代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
<style>
*{
margin: 0;
padding: 0;
border:none
}
img{
vertical-align: top;
}
#box{
width: 350px;
height: 350px;
background-color: red;
margin: 100px 0 0 100px;
position: relative;
}
#small_box{
width: 100%;
height: 100%;
border: 1px solid #ccc;
position: relative;
}
#small_box img{
width: 350px;
height: 350px;
}
#mask{
width: 100px;
height: 100px;
background-color: rgba(255, 255, 0, .4);
position: absolute;
left: 0;
top:0;
cursor: move;
display: none;
}
#big_box{
width: 600px;
height: 600px;
border: 1px solid #ccc;
overflow: hidden;
position: absolute;
left: 360px;
top:0;
display: none;
}
#list{
margin: 20px 0 0 100px;
}
#list img{
margin: 3px;
}
</style>
</head>
<body>
<div id="box">
<div id="small_box">
<img src="images/pic001.jpg" alt="">
<span id="mask"></span>
</div>
<div id="big_box">
<img src="images/pic01.jpg" alt="" style="position: absolute; left:0; top:0;">
</div>
</div>
<div id="list">
<img src="images/pic0001.jpg" alt="">
<img src="images/pic0002.jpg" alt="">
<img src="images/pic0003.jpg" alt="">
</div>
<script>
window.onload = function () {
// 1. 获取需要的标签
var box = document.getElementById("box");
var small_box = box.children[0];
var big_box = box.children[1];
var mask = small_box.children[1];
var big_img = big_box.children[0];
var list_img = document.getElementById("list").children;
// 2. 监听鼠标进入小盒子
small_box.onmouseover = function () {
// 2.1 把隐藏的内容显示
mask.style.display = 'block';
big_box.style.display = 'block';
// 2.2 监听鼠标的移动
small_box.onmousemove = function (event) {
var event = event || window.event;
// 2.3 求出鼠标的座标
var pointX = event.clientX - small_box.offsetParent.offsetLeft - mask.offsetWidth * 0.5;
var pointY = event.clientY - small_box.offsetParent.offsetTop - mask.offsetHeight * 0.5;
// 2.4 边界检测
if(pointX < 0){
pointX = 0;
}else if(pointX >= small_box.offsetWidth - mask.offsetWidth){
pointX = small_box.offsetWidth - mask.offsetWidth;
}
if(pointY < 0){
pointY = 0;
}else if(pointY >= small_box.offsetHeight - mask.offsetHeight){
pointY = small_box.offsetHeight - mask.offsetHeight;
}
// 2.5 让放大镜移动起来
mask.style.left = pointX + 'px';
mask.style.top = pointY + 'px';
// 2.6 让大图移动起来
/*
smallX / bigX = smallBox.width / 大图的宽度
bigX = smallX / ( smallBox.width / 大图的宽度 )
*/
big_img.style.left = - pointX / (small_box.offsetWidth / big_box.offsetWidth) + 'px';
big_img.style.top = - pointY / (small_box.offsetHeight / big_box.offsetHeight) + 'px';
}
};
// 3. 监听鼠标离开小盒子
small_box.onmouseout = function () {
// 2.1 把隐藏的内容显示
mask.style.display = 'none';
big_box.style.display = 'none';
};
// 4. 遍历列表图片
for(var i=0; i<list_img.length; i++){
(function (i) {
var img = list_img[i];
img.onmouseover = function () {
small_box.children[0].src = "images/pic00"+ (i + 1) +".jpg";
big_img.src = "images/pic0"+ (i + 1) +".jpg"
}
})(i);
}
}
</script>
</body>
</html>