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
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