redux - 如何在“待定”状态下在“createAsyncThunk”上发送自定义参数？

Question

何时fetchUserById()创建其输出响应被定义。

const fetchUserById = createAsyncThunk<{user: UserInterface, id: number}, number>(
  'users/fetchByIdStatus',
  async (userId) => {
    const response = await userAPI.fetchById(userId)
    return {user: response.data, id: userId}
  }
);

const userSlice = createSlice({
  name: "users",
  initialState: [],
  reducers: {},
  extraReducers: (builder) => {
    builder.addCase(fetchUserById.pending, (state, { payload }) => {
      // how I configured custom value for this payload?
      // I need to send the user id.
    });
    builder.addCase(fetchUserById.fulfilled, (state, {payload}) => {
      /**
       * @var {UserInterface} user
       * @var {number} id;
       */
      const {id, user} = payload;
      state[id].loading = false;
      state[id].user = user;
    });
  },
});

但是，当操作处于“待处理”状态时，如何定义响应？

Answer 1

您传入的 argcreateAsyncThunk将在action.meta.arg. 因此，在您的示例中，您可以这样引用：

builder.addCase(fetchUserById.pending, (state, { meta }) => {
      console.log(meta.arg); // meta.arg will have whatever value was passed as `userId`
    });