JavaScript拖放效果_html/css

拖动div

【程序说明】

首先初始化函数，对拖放对象添加mousedown监听事件

 initialize:function(drag){ this.Drag = $$(drag);//拖放对象 this._x = this._y = 0;//记录鼠标相对于拖放对象的位置 this._fM = BindAsEventListener(this, this.Move); //绑定拖动时执行的函数 this._fS = Bind(this, this.Stop); //绑定拖动结束执行的函数 this.Drag.style.position = "absolute"; EventUtil.addEventHandler(this.Drag, "mousedown", BindAsEventListener(this, this.Start)); //监听拖动对象mousedown事件 }

之后在Start方法添加mousemove和mouseup事件，分别监听拖放对象的位置和取消监听事件

 Start:function(oEvent){ //记录mousedown触发时鼠标相对于拖放对象的位置 this._x = oEvent.clientX - this.Drag.offsetLeft; this._y = oEvent.clientY - this.Drag.offsetTop; //监听mousemove 和 mouseup事件 EventUtil.addEventHandler(document, "mousemove", this._fM); EventUtil.addEventHandler(document, "mouseup", this._fS); }

完整拖放程序：

 /** *拖放程序 */ var simpleDrag = Class.create(); simpleDrag.prototype = { //初始化对象 initialize:function(drag){ this.Drag = $$(drag);//拖放对象 this._x = this._y = 0;//记录鼠标相对于拖放对象的位置 this._fM = BindAsEventListener(this, this.Move); //绑定拖动时执行的函数 this._fS = Bind(this, this.Stop); //绑定拖动结束执行的函数 this.Drag.style.position = "absolute"; EventUtil.addEventHandler(this.Drag, "mousedown", BindAsEventListener(this, this.Start)); //监听拖动对象mousedown事件 }, //准备拖动 Start:function(oEvent){ //记录mousedown触发时鼠标相对于拖放对象的位置 this._x = oEvent.clientX - this.Drag.offsetLeft; this._y = oEvent.clientY - this.Drag.offsetTop; //监听mousemove 和 mouseup事件 EventUtil.addEventHandler(document, "mousemove", this._fM); EventUtil.addEventHandler(document, "mouseup", this._fS); }, //拖动 Move:function(oEvent){ this.Drag.style.left = oEvent.clientX - this._x + "px"; this.Drag.style.top = oEvent.clientY - this._y + "px"; }, //停止拖动 Stop:function(){ EventUtil.removeEventHandler(document, "mousemove", this._fM); EventUtil.removeEventHandler(document, "mouseup", this._fS); }, }; //初始化拖动 new simpleDrag('drag');

完整DEMO：

    拖动div