https://linyutang.org.tw/big5/js/lazyload.mini.js

1(function($){$.fn.lazyload=function(options){var settings={threshold:0,failurelimit:0,event:"scroll",effect:"show",container:window};if(options){$.extend(settings,options);}
2var elements=this;if("scroll"==settings.event){$(settings.container).bind("scroll",function(event){var counter=0;elements.each(function(){if($.abovethetop(this,settings)||$.leftofbegin(this,settings)){}else if(!$.belowthefold(this,settings)&&!$.rightoffold(this,settings)){$(this).trigger("appear");}else{if(counter++>settings.failurelimit){return false;}}});var temp=$.grep(elements,function(element){return!element.loaded;});elements=$(temp);});}
3this.each(function(){var self=this;if(undefined==$(self).attr("original")){$(self).attr("original",$(self).attr("src"));}
4if("scroll"!=settings.event||undefined==$(self).attr("src")||settings.placeholder==$(self).attr("src")||($.abovethetop(self,settings)||$.leftofbegin(self,settings)||$.belowthefold(self,settings)||$.rightoffold(self,settings))){if(settings.placeholder){$(self).attr("src",settings.placeholder);}else{$(self).removeAttr("src");}
5self.loaded=false;}else{self.loaded=true;}
6$(self).one("appear",function(){if(!this.loaded){$("<img />").bind("load",function(){$(self).hide().attr("src",$(self).attr("original"))
7[settings.effect](settings.effectspeed);self.loaded=true;}).attr("src",$(self).attr("original"));};});if("scroll"!=settings.event){$(self).bind(settings.event,function(event){if(!self.loaded){$(self).trigger("appear");}});}});$(settings.container).trigger(settings.event);return this;};$.belowthefold=function(element,settings){if(settings.container===undefined||settings.container===window){var fold=$(window).height()+$(window).scrollTop();}else{var fold=$(settings.container).offset().top+$(settings.container).height();}
8return fold<=$(element).offset().top-settings.threshold;};$.rightoffold=function(element,settings){if(settings.container===undefined||settings.container===window){var fold=$(window).width()+$(window).scrollLeft();}else{var fold=$(settings.container).offset().left+$(settings.container).width();}

9return fold<=$(element).offset().left-settings.threshold;};$.abovethetop=function(element,settings){if(settings.container===undefined||settings.container===window){var fold=$(window).scrollTop();}else{var fold=$(settings.container).offset().top;}
10return fold>=$(element).offset().top+settings.threshold+$(element).height();};$.leftofbegin=function(element,settings){if(settings.container===undefined||settings.container===window){var fold=$(window).scrollLeft();}else{var fold=$(settings.container).offset().left;}
11return fold>=$(element).offset().left+settings.threshold+$(element).width();};$.extend($.expr[':'],{"below-the-fold":"$.belowthefold(a, {threshold : 0, container: window})","above-the-fold":"!$.belowthefold(a, {threshold : 0, container: window})","right-of-fold":"$.rightoffold(a, {threshold : 0, container: window})","left-of-fold":"!$.rightoffold(a, {threshold : 0, container: window})"});})(jQuery);
12
13jQuery(document).ready(function($){
14  jQuery(".img , .img2").lazyload({
15    effect:"fadeIn",
16	placeholder: "js/lazyload.gif"
17  });
18});