Vant-Weap通过事件获取值

<van-cell-group>
        <van-field
            value="{{username}}"
            label="姓名"
            placeholder="请输入您的姓名"
            bind:blur="getname"
            class='nextnext'
        />
    </van-cell-group>
   <van-button 
      type="primary" size="large" 
      color="linear-gradient(to right, #4bb0ff, #6149f6)"
       bindtap="getalldata"
    > 提交 </van-button>
   -------------------------------------
   ##js##
  data: {
    username:"",
  },
  // 获取姓名
  getname(event) {
    console.log("失去焦点获取的值",event.detail.value);//获取值
    // 设置值
    this.setData({
      username: event.detail.value
    })
  },
  getalldata(){
    console.log("点击按钮获取的值",this.data.username)
  },