(function(a){a.fn.lazyload=function(b){var c={threshold:0,failure_limit:0,event:"scroll",effect:"show",container:window,skip_invisible:!0};b&&(null!==b.failurelimit&&(b.failure_limit=b.failurelimit,delete b.failurelimit),a.extend(c,b));var d=this;return 0==c.event.indexOf("scroll")&&a(c.container).bind(c.event,function(b){var e=0;d.each(function(){if(c.skip_invisible&&!a(this).is(":visible"))return;if(!a.abovethetop(this,c)&&!a.leftofbegin(this,c))if(!a.belowthefold(this,c)&&!a.rightoffold(this,c))a(this).trigger("appear");elseif(++e>c.failure_limit)return!1});var f=a.grep(d,function(a){return!a.loaded});d=a(f)}),this.each(function(){var b=this;b.loaded=!1,a(b).one("appear",function(){this.loaded||a("<img />").bind("load",function(){a(b).hide().attr("src",a(b).data("original"))[c.effect](c.effectspeed),b.loaded=!0}).attr("src",a(b).data("original"))}),0!=c.event.indexOf("scroll")&&a(b).bind(c.event,function(c){b.loaded||a(b).trigger("appear")})}),a(c.container).trigger(c.event),this},a.belowthefold=function(b,c){if(c.container===undefined||c.container===window)var d=a(window).height()+a(window).scrollTop();elsevar d=a(c.container).offset().top+a(c.container).height();return d<=a(b).offset().top-c.threshold},a.rightoffold=function(b,c){if(c.container===undefined||c.container===window)var d=a(window).width()+a(window).scrollLeft();elsevar d=a(c.container).offset().left+a(c.container).width();return d<=a(b).offset().left-c.threshold},a.abovethetop=function(b,c){if(c.container===undefined||c.container===window)var d=a(window).scrollTop();elsevar d=a(c.container).offset().top;return d>=a(b).offset().top+c.threshold+a(b).height()},a.leftofbegin=function(b,c){if(c.container===undefined||c.container===window)var d=a(window).scrollLeft();elsevar d=a(c.container).offset().left;return d>=a(b).offset().left+c.threshold+a(b).width()},a.extend(a.expr[":"],{"below-the-fold":function(b){return a.belowthefold(b,{threshold:0,container:window})},"above-the-fold":function(b){return!a.belowthefold(b,{threshold:0,container:window})},"right-of-fold":function(b){return a.rightoffold(b,{threshold:0,container:window})},"left-of-fold":function(b){return!a.rightoffold(b,{threshold:0,container:window})}})})(jQuery)

window.onload = function(){
    $("img.lazy").lazyload({
      placeholder : "*.gif", //用图片提前占位// placeholder,值为某一图片路径.此图片用来占据将要加载的图片的位置,待图片加载时,占位图则会隐藏
      effect: "fadeIn", // 载入使用何种效果// effect(特效),值有show(直接显示),fadeIn(淡入),slideDown(下拉)等,常用fadeIn
      threshold: 200, // 提前开始加载// threshold,值为数字,代表页面高度.如设置为200,表示滚动条在离目标位置还有200的高度时就开始加载图片,可以做到不让用户察觉
      event: ‘click‘,  // 事件触发时才加载// event,值有click(点击),mouseover(鼠标悬浮),sporty(运动的),foobar(…).可以实现鼠标悬浮或点击图片才开始加载
      container: $("#container"),  // 对某容器中的图片实现效果// container,值为某容器.lazyload默认在拉动浏览器滚动条时生效,这个参数可以让你在拉动某DIV的滚动条时依次加载其中的图片
      failurelimit : 10 // 图片排序混乱时// failurelimit,值为数字.lazyload默认在找到第一张不在可见区域里的图片时则不再继续加载,但当HTML容器混乱的时候可能出现可见区域内图片并没加载出来的情况,failurelimit意在加载N张可见区域外的图片,以避免出现这个问题.    });
}

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