将鼠标事件转换成移动设备触屏事件

            var    mousedown = "mousedown ";//鼠标按下
            var    mousemove = "mousemove ";//鼠标移动
            var    mouseup = "mouseup ";//鼠标抬起
            var  mouseout = "mouseout ";//鼠标移除
            var  mouse='PC';
            if (document.hasOwnProperty("ontouchstart") || 'ontouchstart' in window) {
                mousedown = "touchstart ";//手指按下
                mousemove = "touchmove ";//手指移动
                mouseup = "touchend ";//手指抬起
                mouseout = "touchcancel ";//手指移除
                mouse = 'YD';
            }