(function($) {   /**   * 默認參數   */  var defaultOpts = {   stage: document, //舞臺   item: 'resize-item', //可縮放的類名  };   /**   * 定義類   */  var ZResize = function(options) {   this.options = $.extend({}, defaultOpts, options);   this.init();  }   ZResize.prototype = {   init: function() {    this.initResizeBox();   },   /**    * 初始化拖拽item    */   initResizeBox: function() {    var self = this;    $(self.options.item).each(function () {     //創建面板     var width = $(this).width();     var height = $(this).height();     var resizePanel = $('<div class"resize-panel"></div>');     resizePanel.css({      width: width,      height: height,      top: 0,      left: 0,      position: 'absolute',      'background-color': 'rgba(0,0,0,0.5)',      cursor: 'move',      display: 'none'     });     self.appendHandler(resizePanel, $(this));     /**      * 創建控制點      */     var n = $('<div class="n"></div>');//北     var s = $('<div class="s"></div>');//南     var w = $('<div class="w"></div>');//西     var e = $('<div class="e"></div>');//東     var ne = $('<div class="ne"></div>');//東北     var nw = $('<div class="nw"></div>');//西北     var se = $('<div class="se"></div>');//東南     var sw = $('<div class="sw"></div>');//西南      //添加公共樣式     self.addHandlerCss([n, s, w, e, ne, nw, se, sw]);     //添加各自樣式     n.css({      'top': '-4px',      'margin-left': '-4px',      'left': '50%',      'cursor': 'n-resize'     });     s.css({      'bottom': '-4px',      'margin-left': '-4px',      'left': '50%',      'cursor': 's-resize'     });     e.css({      'top': '50%',      'margin-top': '-4px',      'right': '-4px',      'cursor': 'e-resize'     });     w.css({      'top': '50%',      'margin-top': '-4px',      'left': '-4px',      'cursor': 'w-resize'     });     ne.css({      'top': '-4px',      'right': '-4px',      'cursor': 'ne-resize'     });     nw.css({      top: '-4px',      'left': '-4px',      'cursor': 'nw-resize'     });     se.css({      'bottom': '-4px',      'right': '-4px',      'cursor': 'se-resize'     });     sw.css({      'bottom': '-4px',      'left': '-4px',      'cursor': 'sw-resize'     });      // 添加項目     self.appendHandler([n, s, w, e, ne, nw, se, sw], resizePanel);          //綁定拖拽縮放事件     self.bindResizeEvent(resizePanel, $(this));      //綁定觸發事件     self.bindTrigger($(this));    });    self.bindHidePanel();   },   //控制點公共樣式   addHandlerCss: function(els) {    for(var i = 0; i < els.length; i++) {     el = els[i];     el.css({      position: 'absolute',      width: '8px',      height: '8px',      background: '#ff6600',      margin: '0',      'border-radius': '2px',      border: '1px solid #dd5500',     });    }   },   /**    * 插入容器    */   appendHandler: function(handlers, target) {    for(var i = 0; i < handlers.length; i++) {     el = handlers[i];     target.append(el);    }   },   /**    * 顯示拖拽面板    */   triggerResize: function(el) {    var self = this;    el.siblings(self.options.item).children('div').css({     display: 'none'    });    el.children('div').css({     display: 'block'    });   },   /**    * 拖拽事件控制 包含8個縮放點 和一個拖拽位置    */   bindResizeEvent: function(el) {     var self = this;    var ox = 0; //原始事件x位置    var oy = 0; //原始事件y位置    var ow = 0; //原始寬度    var oh = 0; //原始高度     var oleft = 0; //原始元素位置    var otop = 0;    var org = el.parent('div');     //東    var emove = false;    el.on('mousedown','.e', function(e) {     ox = e.pageX;//原始x位置     ow = el.width();     emove = true;    });     //南    var smove = false;    el.on('mousedown','.s', function(e) {     oy = e.pageY;//原始x位置     oh = el.height();     smove = true;    });     //西    var wmove = false;    el.on('mousedown','.w', function(e) {     ox = e.pageX;//原始x位置     ow = el.width();     wmove = true;     oleft = parseInt(org.css('left').replace('px', ''));    });     //北    var nmove = false;    el.on('mousedown','.n', function(e) {     oy = e.pageY;//原始x位置     oh = el.height();     nmove = true;     otop = parseInt(org.css('top').replace('px', ''));    });     //東北    var nemove = false;    el.on('mousedown','.ne', function(e) {     ox = e.pageX;//原始x位置     oy = e.pageY;     ow = el.width();     oh = el.height();     nemove = true;     otop = parseInt(org.css('top').replace('px', ''));    });     //西北    var nwmove = false;    el.on('mousedown','.nw', function(e) {     ox = e.pageX;//原始x位置     oy = e.pageY;     ow = el.width();     oh = el.height();     otop = parseInt(org.css('top').replace('px', ''));     oleft = parseInt(org.css('left').replace('px', ''));     nwmove = true;    });     //東南    var semove = false;    el.on('mousedown','.se', function(e) {     ox = e.pageX;//原始x位置     oy = e.pageY;     ow = el.width();     oh = el.height();     semove = true;    });     //西南    var swmove = false;    el.on('mousedown','.sw', function(e) {     ox = e.pageX;//原始x位置     oy = e.pageY;     ow = el.width();     oh = el.height();     swmove = true;     oleft = parseInt(org.css('left').replace('px', ''));    });     //拖拽    var drag = false;    el.on('mousedown', function(e) {     ox = e.pageX;//原始x位置     oy = e.pageY;     otop = parseInt(org.css('top').replace('px', ''));     oleft = parseInt(org.css('left').replace('px', ''));     drag = true;    });     $(self.options.stage).on('mousemove', function(e) {     if(emove) {      var x = (e.pageX - ox);      el.css({       width: ow + x      });      org.css({       width: ow + x      });     } else if(smove) {      var y = (e.pageY - oy);      el.css({       height: oh + y      });      org.css({       height: oh + y      });     } else if(wmove) {      var x = (e.pageX - ox);      el.css({       width: ow - x,       // left: oleft + x      });      org.css({       width: ow - x,       left: oleft + x      });     } else if(nmove) {      var y = (e.pageY - oy);      el.css({       height: oh - y,       // top: otop + y      });      org.css({       height: oh - y,       top: otop + y      });     } else if(nemove) {      var x = e.pageX - ox;      var y = e.pageY - oy;      el.css({       height: oh - y,       // top: otop + y,       width: ow + x      });      org.css({       height: oh - y,       top: otop + y,       width: ow + x      });     } else if(nwmove) {      var x = e.pageX - ox;      var y = e.pageY - oy;      el.css({       height: oh - y,       // top: otop + y,       width: ow - x,       // left: oleft + x      });      org.css({       height: oh - y,       top: otop + y,       width: ow - x,       left: oleft + x      });     } else if(semove) {      var x = e.pageX - ox;      var y = e.pageY - oy;      el.css({       width: ow + x,       height: oh + y      });      org.css({       width: ow + x,       height: oh + y      });     } else if(swmove) {      var x = e.pageX - ox;      var y = e.pageY - oy;      el.css({       width: ow - x,       // left: oleft + x,       height: oh + y      });      org.css({       width: ow - x,       left: oleft + x,       height: oh + y      });     } else if(drag) {      var x = e.pageX - ox;      var y = e.pageY - oy;      org.css({       left: oleft + x,       top: otop + y      });     }    }).on('mouseup', function(e) {     emove = false;     smove = false;     wmove = false;     nmove = false;     nemove = false;     nwmove = false;     swmove = false;     semove = false;     drag = false;    });   },   /**    * 點擊item顯示拖拽面板    */   bindTrigger: function(el) {    var self = this;    el.on('click', function(e) {     e.stopPropagation();     self.triggerResize(el);    });   },   /**    * 點擊舞臺空閑區域 隱藏縮放面板    */   bindHidePanel: function(el) {    var stage = this.options.stage;    var item = this.options.item;    $(stage).bind('click', function() {     $(item).children('div').css({      display: 'none'     });    })   }  }   window.ZResize = ZResize;  })(jQuery); 

<!doctype html> <html>  <head>  <meta charset="utf-8">  <title>jQuery拖拽放大縮小插件idrag</title>  <meta http-equiv="Content-Type" content="text/html; charset=utf-8">  <style type="text/css">  .item1 {   width: 405px;   height: 291px;   cursor: move;   position: absolute;   top: 30px;   left: 30px;   background-color: #FFF;   border: 1px solid #CCCCCC;   -webkit-box-shadow: 10px 10px 25px #ccc;   -moz-box-shadow: 10px 10px 25px #ccc;   box-shadow: 10px 10px 25px #ccc;  }    .item2 {   width: 200px;   height: 100px;   cursor: move;   position: absolute;   top: 400px;   left: 100px;   background-color: #FFF;   border: 1px solid #CCCCCC;   -webkit-box-shadow: 10px 10px 25px #ccc;   -moz-box-shadow: 10px 10px 25px #ccc;   box-shadow: 10px 10px 25px #ccc;   line-height: 100px;   text-align: center;  }    body {   background-color: #F3F3F3;  }  </style> </head>  <body>  <div id="mydiv" style="width:800px; height:800px; border-style:solid">   <div id="div1" class="resize-item item1">    <img src="images/dog.png" width="100%" height="100%">   </div>   <div class="resize-item item2">    你是我的小小狗   </div>  </div>  <script src="jquery.min.js"></script>  <script type="text/javascript" src='jquery.ZResize.js'></script>  <script type="text/javascript">   new ZResize({    stage: "#mydiv", //舞臺    item: '#div1', //可縮放的類名   });  </script> </body>  </html>