怎样用H5计算手机摇动次数

var jsonObject=null;
 // 当页面加载完以后会执行window.onload
 window.onload = function() {
 var times = -1; // 记录摇动次数
 var last_time = 0;
 var borderSpeed = 800; // 加速度变化临界值
 var x = y = z = last_x = last_y = last_z = 0;
 if (window.DeviceMotionEvent) {
 window.addEventListener('devicemotion',shake,false);
 }
 else
 {
 alert('您的设备不支持摇一摇哦');
 }
 // 每次手机移动的时候都会执行下面shake函数的代码
 function shake(eventData)
 {
 var acceleration = eventData.accelerationIncludingGravity;
 var curTime = new Date().getTime();
 var diffTime = curTime-last_time;
 // 每隔100ms进行判断
 if (diffTime>100) {
 x = acceleration.x;
 y = acceleration.y;
 z = acceleration.z;
 var speed = Math.abs(x + y + z - last_x - last_y - last_z) / diffTime * 10000;
 // 判断手机确实发生了摇动而不是正常的移动
 if (speed>borderSpeed) {
 times++;
 document.getElementById("text").innerHTML=times+" times";
 // 用户的微信昵称和头像连接发送一次即可，不需要每次都发送
 if (times==0)
 {
 document.forms["insertForm"].headimg.value =img ;
 document.forms["insertForm"].user.value = nickname;
 }
 document.forms["insertForm"].time.value = times;
 }
 last_time = curTime;
 last_x = x;
 last_y = y;
 last_z = z;
 }
 }
 }

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