Drag and drop to move the dom

				dom.onmousedown = function (e) {
    
    
                    that.ismove = false
                    document.onmousemove = function (e) {
    
    
                        that.ismove = true
                        that.move(e) //拖动处理 比如重新定义位置
                    };
                    document.onmouseup = function () {
    
    
                        if(!that.ismove){
    
    
                            that.handler() // 是点击事件 处理点击事件
                        }
                        that.ismove = false
                        document.onmousemove = null;
                        document.onmouseup = null;
                        that.check() //可以检测移动的位置 控制定位
                    };
                    return false;
                };