Vue关于beforeRouteEnter以及beforeRouteLeave函数的运用

beforeRouteEnter:(to,from,next)=>{

    console.log("进入路由之前")
    next(vm =>{
      vm.getData();
    });
  },
  beforeRouteLeave:(to,from,next)=>{
      console.log("进入路由之后")
      next();
  },
  methods:{
    getData:function (){
      this.axios({
        method:"get",
        url:"http://localhost:8081/static/mock/data.json"
      }).then(function (response){
        console.log(response)
      })
    }
  }