缓冲图片 loading.gif ：
需缓冲图片js引用 ：
<script type="text/javascript" src="jquery-1.9.1.min.js"></script>
<script type="text/javascript" src="jquery.lazyload.min.js"></script>
(function($){
$("img.lazy").show().lazyload({effect: "fadeIn"});
})(jQuery);
***jquery.lazyload.min.js***
/* * Lazy Load - jQuery plugin for lazy loading images * * Copyright (c) 2007-2012 Mika Tuupola * * Licensed under the MIT license: * http://www.opensource.org/licenses/mit-license.php * * Project home: * http://www.appelsiini.net/projects/lazyload * * Version: 1.7.2 * */ (function(a,b){$window=a(b),a.fn.lazyload=function(c){function f(){var b=0;d.each(function(){var c=a(this);if(e.skip_invisible&&!c.is(":visible"))return;if(!a.abovethetop(this,e)&&!a.leftofbegin(this,e))if(!a.belowthefold(this,e)&&!a.rightoffold(this,e))c.trigger("appear");else if(++b>e.failure_limit)return!1})}var d=this,e={threshold:0,failure_limit:0,event:"scroll",effect:"show",container:b,data_attribute:"original",skip_invisible:!0,appear:null,load:null};return c&&(undefined!==c.failurelimit&&(c.failure_limit=c.failurelimit,delete c.failurelimit),undefined!==c.effectspeed&&(c.effect_speed=c.effectspeed,delete c.effectspeed),a.extend(e,c)),$container=e.container===undefined||e.container===b?$window:a(e.container),0===e.event.indexOf("scroll")&&$container.bind(e.event,function(a){return f()}),this.each(function(){var b=this,c=a(b);b.loaded=!1,c.one("appear",function(){if(!this.loaded){if(e.appear){var f=d.length;e.appear.call(b,f,e)}a("<img />").bind("load",function(){c.hide().attr("src",c.data(e.data_attribute))[e.effect](e.effect_speed),b.loaded=!0;var f=a.grep(d,function(a){return!a.loaded});d=a(f);if(e.load){var g=d.length;e.load.call(b,g,e)}}).attr("src",c.data(e.data_attribute))}}),0!==e.event.indexOf("scroll")&&c.bind(e.event,function(a){b.loaded||c.trigger("appear")})}),$window.bind("resize",function(a){f()}),f(),this},a.belowthefold=function(c,d){var e;return d.container===undefined||d.container===b?e=$window.height()+$window.scrollTop():e=$container.offset().top+$container.height(),e<=a(c).offset().top-d.threshold},a.rightoffold=function(c,d){var e;return d.container===undefined||d.container===b?e=$window.width()+$window.scrollLeft():e=$container.offset().left+$container.width(),e<=a(c).offset().left-d.threshold},a.abovethetop=function(c,d){var e;return d.container===undefined||d.container===b?e=$window.scrollTop():e=$container.offset().top,e>=a(c).offset().top+d.threshold+a(c).height()},a.leftofbegin=function(c,d){var e;return d.container===undefined||d.container===b?e=$window.scrollLeft():e=$container.offset().left,e>=a(c).offset().left+d.threshold+a(c).width()},a.inviewport=function(b,c){return!a.rightofscreen(b,c)&&!a.leftofscreen(b,c)&&!a.belowthefold(b,c)&&!a.abovethetop(b,c)},a.extend(a.expr[":"],{"below-the-fold":function(c){return a.belowthefold(c,{threshold:0,container:b})},"above-the-top":function(c){return!a.belowthefold(c,{threshold:0,container:b})},"right-of-screen":function(c){return a.rightoffold(c,{threshold:0,container:b})},"left-of-screen":function(c){return!a.rightoffold(c,{threshold:0,container:b})},"in-viewport":function(c){return!a.inviewport(c,{threshold:0,container:b})},"above-the-fold":function(c){return!a.belowthefold(c,{threshold:0,container:b})},"right-of-fold":function(c){return a.rightoffold(c,{threshold:0,container:b})},"left-of-fold":function(c){return!a.rightoffold(c,{threshold:0,container:b})}})})(jQuery,window)
***html***
<!DOCTYPE html> <html> <head> <title></title> <script type="text/javascript" src="jquery-1.9.1.min.js"></script> <script type="text/javascript" src="jquery.lazyload.min.js"></script> <style type="text/css"> img.lazy { display: none; }<!--默认图片不显示-->
</style> </head>
<body>
<div style="800px; margin:10px auto;">
<img class="lazy" src="loading.gif" data-original="Banner3.jpg" width="800" height="250"/> <!--需定交图片大小，预留空间--> <img class="lazy" src="loading.gif" data-original="Banner.jpg" width="800" height="250"/> <img class="lazy" src="loading.gif" data-original="banner01_42.jpg" width="800" height="250"/> <img class="lazy" src="loading.gif" data-original="Banner1.jpg" width="800" height="250"/> <img class="lazy" src="loading.gif" data-original="Banner2.jpg" width="800" height="250"/> </div> <script> (function($){ $("img.lazy").show().lazyload({effect: "fadeIn"}); })(jQuery); </script> </body> </html>