npm install --save @riophae/vue-treeselect

 <template>
 <el-form ref="form"
           :model="searchForm"
           label-width="100px"
           :inline="true"
           :size="$formSize">
    <el-form-item label="區(qū)域：">
    <!--使用此插件過(guò)程中發(fā)現(xiàn)了一個(gè)新的問題，可能會(huì)因?yàn)閷蛹?jí)樣式問題在element組件中無(wú)法展示選項(xiàng)-->
    <!--修改方法就是將append-to-body的綁定值改為false-->
      <treeselect :append-to-body="true"
                  v-model="searchForm.areaId"
                  :options="areaAllList"
                  :normalizer="normalizer"
                  :show-count="true"
                  placeholder="請(qǐng)選擇所屬區(qū)域" />
    </el-form-item>
 </el-form>
 </template>

<script>
//引入插件
import Treeselect from "@riophae/vue-treeselect";
import "@riophae/vue-treeselect/dist/vue-treeselect.css";
export default {
  //使用組件
  components: { Treeselect },
  data () {
    return {
      areaAllList: [],
      searchForm: {
        areaId: null,//綁定值必須為null,否則輸入框中會(huì)提示unkonwn
      },
    }
  },
  mounted () {
    this.getAreaAll()
  },
  methods: {
    //轉(zhuǎn)換菜單數(shù)據(jù)結(jié)構(gòu)
    normalizer (node) {
      if (node.children && !node.children.length) {
        delete node.children;
      }
      return {
        id: node.areaId,
        label: node.areaName,
        children: node.children,
      };
    },
    //調(diào)用接口獲取select選項(xiàng)數(shù)據(jù)
    getAreaAll () {
      request({
        url: `/manager/Area/AllAreaTree`,
        method: "get",
      }).then((res) => {
        if (res[SETTING.MANAGER_STATE] === SETTING.MANAGER_SUCCESS_STATE) {
          this.areaAllList = res.data;
        } else {
          this.$message({
            type: "error",
            message: res.message || "操作失敗",
          });
        }
      });
    },
  }
}
</script>

<style lang="scss" scoped>
::v-deep .vue-treeselect__control {
  max-width: 215px;
}
</style>