这是子组件中:
<v-form-item class="pwd reg-cell" required :label="showlabel" prop="vertifyCode">

  <v-input v-model="vertifyCode" @change="send()" name="vertifyCode" placeholder="6位数字手机验证码"></v-input>
  <button type="button" class="uploadfile" id="getcode" @click="getcode">{{SMSCode}}</button>
</v-form-item>

methods:{

  //发送验证码
getcode(){
  this.intverTime = 10;
  var $up = $('#getcode');
  this.sentime =setInterval(() => {
    if ( this.intverTime > 0) {
      this.intverTime = this.intverTime -1;
      this.SMSCode = this.intverTime + "s 后重试";
      $up.attr("disabled",true);  
    } else {
      $up.attr("disabled",false);  
      this.SMSCode = "获取验证码";
      clearInterval(this.sentime);
      this.intverTime = 10;
      this.isloading = false;
    }
  }, 1000);
  post(this, api.sendCode, {'phoneNumber': this.phoneNumber }, (response) => {
    if (response.code == 0) {
      // callback();
      console.log('获取验证码成功');
    } else {
      this.SMSCode = "获取验证码";
      // clearInterval(this.sentime);
      this.intverTime = 10;
      this.isloading = false;
    }
  });
},
send(){
  console.log(this.vertifyCode);   //没有打印值，说明change事件没有触发，值发送不到父组件中去
  this.$emit('getVal',this.vertifyCode);
  // this.$emit('child-info',this.msgChild)
}

},

//父组件中
<v-getcode @getVal="phonecode" :phoneNumber="registerParams.phoneNumber" ></v-getcode>
methods: {

phonecode(val){
  console.log('接收子组件传过来的code值：'+val);
  this.registerParams.vertifyCode = val;
},

}