懒加载
1 <style>
2 img a,img{border:0px;}
3 div{ margin-bottom:10px;}
4 </style>
5 <!--
6 一、为什么需要懒加载？
7 对于图片过多的使用场景，为了提高页面加载速度，改善用户体验，我们对未出现在视野范围内的图片先不进行加载，等到出现在视野范围才去加载。
8 二、懒加载的实现原理
9 -它的实现原理很简单，先把img的src指向一个小图片，图片真实的地址存储在img一个自定义的属性里,,等到此图片出现在视野范围内了，获取img元素，把data-src里的值赋给src。
10 -->
11 <body>
12 <img src="images/1.jpg" />
13 <br />
14 <div><a href="#"><img src="images/zhuan.gif" data-original="images/1.jpg"></a></div>
15 <div><a href="#"><img src="images/zhuan.gif" data-original="images/2.jpg"></a></div>
16 <div><a href="#"><img src="images/zhuan.gif" data-original="images/3.jpg"></a></div>
17 <div><a href="#"><img src="images/zhuan.gif" data-original="images/4.jpg"></a></div>
18 <div><a href="#"><img src="images/zhuan.gif" data-original="images/5.jpg"></a></div>
19 <div><a href="#"><img src="images/zhuan.gif" data-original="images/6.jpg"></a></div>
20 <div><a href="#"><img src="images/zhuan.gif" data-original="images/7.jpg"></a></div>
21 <div><a href="#"><img src="images/zhuan.gif" data-original="images/8.jpg"></a></div>
22 <div><a href="#"><img src="images/zhuan.gif" data-original="images/9.jpg"></a></div>
23 <div><a href="#"><img src="images/zhuan.gif" data-original="images/10.jpg"></a></div>
24 </body>
25 </html>
26 <script src="jquery-1.11.1.js"></script>
27 <script src="jquery.lazyload.min.js"></script>
28 <script>
29 $(function() {
30 $("img").lazyload({
31 placeholder : "images/loading.gif",
32 effect: "fadeIn"
33 });
34 });
35 </script>
自引jquery
jquery.lazyload.min.js
/*! Lazy Load 1.9.7 - MIT license - Copyright 2010-2015 Mika Tuupola */
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