HTML

<div class="page-datetime">
      <div class="page-datetime-wrapper">
        <mt-button @click.native="open('picker')" size="large">点击弹出{{msg}}</mt-button>
        <p>{{msg}}</p>
      </div class="page-datetime-wrapper">
      <mt-datetime-picker ref="picker" type="datetime" v-model="value" @confirm="handleChange"></mt-datetime-picker>
  </div>

JS 部分

data() {
    return {
      value: null,
      msg: new Date().toLocaleString().slice(0, length - 3),
    }
  }
methods:{
    open() {
      this.$refs.picker.open();
    },
    handleChange(value) {
      this.msg = value.toLocaleString().slice(0, length - 3);
    }
}