elementui树形控件使用细节

<el-tree
              class="el-tree-section"
              :data="firstTreeData"
              show-checkbox
              node-key="outerCompanyOrgCode"
              default-expand-all
              :default-checked-keys="oneLevelTreeCheckedKeys"
              :props="defaultProps"
              @check="handleCheckChangeFirst"
            >
            </el-tree>


//lable 除了正常配置 还可以这样扩展
 vue data对象里：
      defaultProps: {
        children: 'children',
        label: function (data, node) {
          return '[' + data.outerCompanyOrgCode + ']' + data.mchCompanyOrgName;
        },
      },


methods:里
/**获取树形数据--基础数据 */
    getMchShareRelGetCompanyTree() {
      let params = { skuOwnMchId: this.currentTableItem.skuOwnerMchId };
      API.adoptPin.mchShareRelGetCompanyTree(params).then((res) =&