TypeError：未定义不是函数（评估'categories.map'）

Question

嗨，我有这样的 json 文件

[
  {
    "id": 1,
    "code":"films",
    "name":"FILMS",
    "icon":"film",
    "image":"http://static.tvmaze.com/uploads/images/large_landscape/137/343398.jpg",
    "subs": [
      {
        "id": "1-1",
        "code": "553",
        "name": "films 1",
      },
      {
        "id": "1-2",
        "code": "554",
        "name": "film 2",
      }
    ]
  },
  {
    "id": 2,
    "code":"series",
    "name":"SERIES",
    "icon":"television",
    "image":"http://static.tvmaze.com/uploads/images/large_landscape/142/356297.jpg",
    "subs": [
      {
        "id": "2-1",
        "code": "555",
        "name": "series 1",
      },
      {
        "id": "2-2",
        "code": "556",
        "name": "series 2",
      }
    ]
  }
]

我正在使用 redux (axios) 获取它

// CATEGORIES
export function retrieveCategoriesSuccess(res) {
    return {
        type: types.RETRIEVE_MOVIES_CATEGORIES_SUCCESS,
        categories: res.data
    };
}
export function retrieveMoviesCategories() {
    return function (dispatch) {

        return axios.get(FETCHING_MOVIES_URL + "data/categories.json")
        .then(res => {
            dispatch(retrieveCategoriesSuccess(res));
        })
        .catch(error => {
            console.log("Categories: ", error); //eslint-disable-line
        });
    };
}

我尝试以这种方式将其映射到我的菜单：

    //return categories.map((obj) => (
    return this.props.categories.map((obj, key) => {
        <View key={obj.id}>
            <Text style={styles.text}>{obj.name}</Text>
        </View>
        {_renderSubMenu(obj)}
    })

当我删除 subs 数组时，代码效果很好，我得到了菜单列表，但是当我添加子类别时，我得到了这个错误： TypeError: TypeError: undefined is not a function (evalating 'categories.map')

Console.log(this.props.categories) 前map bloc显示json数据， 我也试过 return categories.map((obj) =>... 但也没有用

Answer 1

对于遇到此类问题的任何人，请检查 json 文件中的尾随逗号。