(function($){ $.fn.zoom = function(settings){ //一些默认配置； settings = $.extend({ height:0, width:0, loading:"lightbox-ico-loading.gif" },settings); var images = this; $(images).hide(); var loadding = new Image(); loadding.className="loadding" loadding.src = settings.loading; $(images).after(loadding); //预加载 var preLoad = function($this){ var img = new Image(); img.src = $this.src; if (img.complete) { processImg.call($this); return; } //$this.src = loadding.src;//会导致获取错误的尺寸 img.onload = function(){ //$this.src = this.src; //会导致获取错误的尺寸 processImg.call($this); img.onload=function(){}; } } //计算图片尺寸； function processImg(){ //if(settings.height===0||settings.width ===0) return; var m = this.height-settings.height; var n = this.width - settings.width; if(m>n) this.height = this.height>settings.height ? settings.height : this.height; else this.width = this.width >settings.width ? settings.width : this.width; $(this).next(".loadding").remove() $(this).show(); } return $(images).each(function(){ preLoad(this); }); } })(jQuery);