1.  
   <script>

2.  
    
3.  
   //返回角度

4.  
   function GetSlideAngle(dx, dy) {

5.  
   returnMath.atan2(dy, dx) *
   180 / Math.PI;

6.  
   }

7.  
    
8.  
   //根据起点和终点返回方向 1：向上，2：向下，3：向左，4：向右,0：未滑动

9.  
   function GetSlideDirection(startX, startY, endX, endY) {

10.  
    var dy = startY - endY;

11.  
    var dx = endX - startX;

12.  
    varresult =
    0;

13.  
     
14.  
    //如果滑动距离太短

15.  
    if(Math.abs(dx) < 2 && Math.abs(dy) < 2) {

16.  
    returnresult;

17.  
    }

18.  
     
19.  
    varangle = GetSlideAngle(dx, dy);

20.  
    if(angle >= -45 && angle < 45) {

21.  
    result =
    4;

22.  
    }
    else if (angle >= 45 && angle < 135) {

23.  
    result =
    1;

24.  
    }
    else if (angle >= -135 && angle < -45) {

25.  
    result =
    2;

26.  
    }

27.  
    else if ((angle >= 135 && angle <= 180) || (angle >= -180 && angle < -135)) {

28.  
    result =
    3;

29.  
    }

30.  
     
31.  
    returnresult;

32.  
    }

33.  
     
34.  
    //滑动处理

35.  
    var startX, startY;

36.  
    document.addEventListener(‘touchstart‘,function (ev) {

37.  
    startX = ev.touches[
    0].pageX;

38.  
    startY = ev.touches[
    0].pageY;

39.  
    },
    false);

40.  
    document.addEventListener(‘touchend‘,function (ev) {

41.  
    var endX, endY;

42.  
    endX = ev.changedTouches[
    0].pageX;

43.  
    endY = ev.changedTouches[
    0].pageY;

44.  
    var direction = GetSlideDirection(startX, startY, endX, endY);

45.  
    switch(direction) {

46.  
    case 0:

47.  
    alert(
    "没滑动");

48.  
    break;

49.  
    case 1:

50.  
    alert(
    "向上");

51.  
    break;

52.  
    case 2:

53.  
    alert(
    "向下");

54.  
    break;

55.  
    case 3:

56.  
    alert(
    "向左");

57.  
    alert(
    "!");

58.  
    break;

59.  
    case 4:

60.  
    alert(
    "向右");

61.  
    break;

62.  
    default:

63.  
    }

64.  
    },
    false);

65.  
     
66.  
     
67.  
    </script>

68.  

转载：https://blog.csdn.net/iwasdream/article/details/33741859