图片根据鼠标滚动延时加载

最近研究了京东商城用jQuery的实现如下：

就是默认地址赋给img标签的src2属性，显示时赋给src属性值。

function lazyload(option) {

    var settings = {

defObj: null,

defHeight: 0

    };

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

    var defHeight = settings.defHeight;

    var 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");

//已显示的不用再显示

if (src2) {

                    //显示后，去掉src2属性

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

}

            }

});

    };

    imgLoad();

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

        imgLoad();

    });

}

lazyload({

    defObj:".w1"

});

摘自 pcenshao