WeChat applet implements countdown for sending SMS verification code

<view class="container">
  <view class="userinfo">
    <image class="userinfo-avatar" src="../../images/timg.jpg" mode="cover"></image>
    <text class="userinfo-nickname">What</text>
  </view>
  <view class="wrap">
    <view class="tel">
      <input type="number" bindinput="bindTelInput" maxlength="11" 
         placeholder="Please enter your phone number"
         placeholder-style="color:#C3C6C4;"/>
    </view>
    <view class="ver-code">
      <view class="code">
        <input type="number" bindinput="bindCodeInput" maxlength="6"
               placeholder="Please enter the verification code"
               placeholder-style="color:#C3C6C4;"/>
      </view>
      <view class="getCode" bindtap="getCode" wx:if="{{countDownNum == 60 || countDownNum == -1}}">
        <button type="primary" plain="true">Get verification code</button>
      </view>
      <view class="getCode" wx:else>
        <button type="primary" plain="true">Re-acquire after {{countDownNum}}s</button>
      </view>
    </view>
  </view>
  <view class="btn-login" bindtap="login">Login</view>
</view>

//Get the application instance const app = getApp()

Page({

  /**
   * Initial data of the page */
  data: {
    phone: null, // Phone number code: null, // Phone verification code countDownNum: 60, // Countdown initial value },

  /**
   * Life cycle function--listen for page loading*/
  onLoad: function (options) {

  },

  /**
   * Life cycle function--monitor page display*/
  onShow: function () {
    
  },
  
  /**
   * Life cycle function - listen for the completion of the initial rendering of the page*/
  onReady: function () {

  },
  
  /**
   * User clicks on the upper right corner to share*/
  onShareAppMessage: function () {

  },
  // Input phone number bindTelInput: function (e) {
    this.setData({
      phone: e.detail.value
    })
  },
  // Input verification code bindCodeInput: function (e) {
    this.setData({
      code: e.detail.value
    })
  },
  // Send mobile verification codegetCode: function () {
    if (!!this.data.phone) {
      if (!!(/^1[34578]\d{9}$/.test(this.data.phone))) {
        wx.showToast({
          title: "Sent successfully",
          icon: "none",
          duration: 1500
        })
        this.countDown()
      } else {
        wx.showToast({
          title: "Please enter a valid mobile phone number",
          icon: "none",
          duration: 1500
        })
      }
    } else {
      wx.showToast({
        title: "Please enter your mobile number",
        icon: "none",
        duration: 1500
      })
    }
  },
  /**
   * Verification code countdown*/
  countDown: function () {
    var _this = this
    var countDownNum = _this.data.countDownNum // Get the countdown initial value var timer = setInterval(function () {
      countDownNum -= 1
      _this.setData({
        countDownNum: countDownNum
      })
      if (countDownNum <= -1) {
        clearInterval(timer)
        // Unpin the code that the setInterval function will execute_this.setData({
          countDownNum: 60
        })
      }
    }, 1000)
  },
  // Mobile phone verification code login: function () {
    if (this.data.phone) {
      if (!!(/^1[34578]\d{9}$/.test(this.data.phone))) {
        if (this.data.code) {
          wx.showToast({
            title: "Login successful",
            icon: "none",
            duration: 1500
          })
        } else {
          wx.showToast({
            title: "Please enter the verification code",
            icon: "none",
            duration: 1500
          })
        }
      } else {
        wx.showToast({
          title: "Please enter a valid mobile phone number",
          icon: "none",
          duration: 1500
        })
      }
    } else {
      wx.showToast({
        title: "Please enter your mobile number",
        icon: "none",
        duration: 1500
      })
    }
  }
})

.userinfo {
  height: 240rpx;
  margin: 40rpx auto 0;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.userinfo .userinfo-avatar {
  width: 140rpx;
  height: 140rpx;
  margin: 20rpx;
  border-radius: 50%;
  border: 1rpx solid #dad5d5;
}

.userinfo .userinfo-nickname {
  color: #aaa;
}

.wrap {
  width: 630rpx;
  font-size: 32rpx;
  margin: 80rpx auto 120rpx;
}

.wrap .tel {
  width: 100%;
  height: 68rpx;
  border-bottom: 1rpx solid #DDE3EC;
  margin-bottom: 60rpx;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
}

.wrap .ver-code {
  width: 100%;
  height: 68rpx;
  border-bottom: 1rpx solid #DDE3EC;
  display: flex;
  justify-content: space-between;
}

.wrap .ver-code .code {

}

.wrap .ver-code .getCode {
  min-width: 190rpx;
  height: 40rpx;
}

.wrap .ver-code .getCode button {
  width: 100%;
  height: 100%;
  font-size: 28rpx;
  font-weight: normal;
  line-height: 40rpx;
  background: #fff;
  color: #ffaa7f;
  border: none;
  padding: 0;
  margin: 0;
}

.btn-login {
  width: 588rpx;
  height: 88rpx;
  background: #ffaa7f;
  border-radius: 10rpx;
  text-align: center;
  line-height: 88rpx;
  font-size: 36rpx;
  font-weight: 500;
  color: #fff;
  margin: 0 auto;
}

.clickClass {
  background: #ea986c;
}