整理文檔，搜刮出一個vue 計時器組件的代碼，稍微整理精簡一下做下分享。

<template> <div>  <span     :sendSync="sendSync"     :autoStart="autoStart"     :defaultVal="defaultVal"  >{{countString}}</span> </div></template><script>export default { data() {  return {   isStart: false,   globalTimer: null,//獲取setInterval對象值   countString: '0秒', //用來顯示時間   day: 0,   hour: 0,   minute: 0,   second: 0,   millisecond: 0,   countVal: this.defaultVal, //獲取初始值   pauseTime: 0,  } }, watch: {  'countString': {   deep: true,   handler: function(val, oldVal) {    var vm = this    if (vm.needSendSunc) {     vm.passToParent(val)    }   }  },  'needSendSunc': {   deep: true,   handler: function(val) {    var vm = this    if (val) {     vm.passToParent(vm.countString)    }   }  } }, props: {  sendSync: {   type: Boolean,   default: false,  },  autoStart: {   type: Boolean,   default: false,  },  defaultVal: {   type: Number,   default: 0,  } }, mounted() {  var vm = this  if (vm.autoStart) {   vm.startCountFn()  } }, computed: {  needSendSunc: function() {   return this.sendSync  } }, created: function() {  this.$on('startCount', function() {   this.startCountFn()  });  this.$on('stopCount', function() {   this.stopCountFn()  }); }, components: {}, methods: {  counterFn: function(counterTime) {   var vm = this   var nowDate = new Date().getTime()   if(vm.pauseTime == 0){    var num = nowDate - counterTime //計算時間毫秒差   }else{    vm.pauseTime = vm.pauseTime +10    var num = vm.pauseTime - counterTime //計算時間毫秒差   }   var leave1 = num % (24 * 3600 * 1000)  //計算天數(shù)后剩余的毫秒數(shù)   var leave2 = leave1 % (3600 * 1000)    //計算小時數(shù)后剩余的毫秒數(shù)   var leave3 = leave2 % (60 * 1000)   //計算分鐘數(shù)后剩余的毫秒數(shù)   vm.day = Math.floor(num / (24 * 3600 * 1000)) //計算相差天數(shù)   vm.hour = Math.floor(leave1 / (3600 * 1000))//計算相差小時   vm.minute = Math.floor(leave2 / (60 * 1000))//計算相差分鐘   vm.second = Math.round(leave3 / 1000) //計算相差秒   if (vm.day > 0) {    vm.countString = `${vm.day}天 ${vm.hour}小時 ${vm.minute}分 ${vm.second}秒`;   } else if (vm.hour > 0) {    vm.countString = `${vm.hour}小時 ${vm.minute}分 ${vm.second}秒`;   } else if (vm.minute > 0) {    vm.countString = `${vm.minute}分 ${vm.second}秒`;   } else {    vm.countString = `${vm.second}秒`;   }  },  startCountFn: function() {   var vm = this   if (!vm.isStart) {    vm.countVal = vm.countVal ? vm.countVal : new Date().getTime()    var timer = setInterval(function() {     vm.counterFn(vm.countVal)    }, 10)    vm.globalTimer = timer    vm.isStart = true   }  },  stopCountFn: function() {   var vm = this   if (vm.isStart) {    window.clearInterval(vm.globalTimer)    vm.globalTimer = null;    vm.isStart = false    vm.pauseTime = new Date().getTime()   }  },  passToParent: function(data) {   var vm = this   this.$emit("getDataFromChild", data)  }, }}</script><style></style>