以下是实现代码(基于jquery): 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();