以下是实现代码(基于jquery):

复制代码 代码如下:

function lazyload(option){

var settings={

defObj:null,

defHeight:0

};

settings=$.extend(settings,option||{});

var defHeight=settings.defHeight,defObj=(typeof settings.defObj=="object")?settings.defObj.find("img"):$(settings.defObj).find("img");

var pageTop=function(){

return document.documentElement.clientHeight+Math.max(document.documentElement.scrollTop,document.body.scrollTop)-settings.defHeight;

};

var imgLoad=function(){

defObj.each(function(){

if ($(this).offset().top<=pageTop()){

var src2=$(this).attr("src2");

if (src2){

$(this).attr("src",src2).removeAttr("src2");

}

}

});

};

imgLoad();

// 绑定滚动事件

$(window).bind("scroll",function(){

imgLoad();

});

}

lazyload({

defObj:"#plist"

})