$.fn.popImg = function() {  //your code goes here}

;(function($,window,document,undefined){  $.fn.popImg = function() {   //your code goes here  }})(jQuery,window,document);

;(function($,window,document,undefined){ $.fn.popImg = function(){   //創建彈出層   var $layer = $("<div>").css({    position:'fixed',    left:0,    right:0,    top:0,    bottom:0,    width:'100%',    height:'100%',    zIndex:9999999,    display:'none',    background: "#000",    opacity:'0.6'   });   //復制點擊的圖片，獲得圖片的寬高以及位置   var cloneImg = function($targetImg){     var cloneW = $targetImg.width(),       cloneH = $targetImg.height(),       left = $targetImg.offset().left,       top = $targetImg.offset().top;     return $targetImg.clone().css({       position:'fixed',       width:cloneW,       height:cloneH,       left:left,       top:top,       zIndex:10000000     });   };   //讓復制的圖片居中顯示   var centerImg = function($cloneImg){     var dW = $(window).width();     var dH = $(window).height();     $cloneImg.css('cursor','zoom-out').attr('clone-bigImg',true);     var img = new Image();     img.onload = function(){      $cloneImg.stop().animate({         width: this.width,        height: this.height,        left: (dW - this.width) / 2,        top: (dH - this.height) / 2      },300);     }     img.src = $cloneImg.attr('src');   };   this.each(function(){     $(this).css('cursor','zoom-in').on('click',function(){       var $body = $("body");       $layer.appendTo($body);       $layer.fadeIn(300);       var $c = cloneImg($(this));       $c.appendTo($body);       centerImg($c);     });   });  var timer = null;  $(window).on("resize", function(){   $("img[clone-bigImg]").each(function(){    var $this = $(this);    timer && clearTimeout(timer);    timer = setTimeout(function(){     centerImg($this);    }, 10);   });  });  $(window).on("click keydown", function(evt){   if(evt.type == "keydown" && evt.keyCode === 27) {    $layer.fadeOut(300);    $("img[clone-bigImg]").remove();   }   var $this = $(evt.target);   if($this.attr("clone-bigImg")){    $layer.fadeOut(300);    $("img[clone-bigImg]").remove();   }  }); }})(jQuery,window,document);