post傳參的時候categorys 為啥不能識別呢？

代碼貼在下面：

<script>
export default {
  name: "app",
  components: {},
  data() {
    return {
      banner: require("@/assets/hottopic/banner.png"),
      data: [],
      filter: {
        page: {
          pageSize: 5,
          pageNumber: 1,
          totalSize: 100
        },
        categorys: ["小微企業(yè)專題"]
      }
    };
  },
  computed: {},
  methods: {
    getData() {
      this.filter.categorys = ["this.$route.params.id"]
      this.$API.post("/articlelist/query", this.filter).then(res => {
        console.log(res);
        this.data = res.list;
      });
    }
  },
  created() {
    if(this.$route.params.id){
      this.getData();
    }
  },
  mounted() {},
  watch:{
    "$route":"getData"
  }
};
</script>