反应redux中间件调度2动作

Question

The first chunk as an action creator below works as is with thunk, but I want to also apply the 2nd chunk, which is a promise middleware. How do I tweak it so that it can dispatch 2 actions?

export const fetchPokemon = function (pokemonName) {
  return function (dispatch) {
    dispatch({type: 'REQUESTING'})
    const requestURL = `http://pokeapi.co/api/v2/pokemon/${pokemonName}/`
    return fetch(requestURL)
    .then(function (response) {
      return response.json()
    })
    .then(function (data) {
      dispatch(receivePokemon(formatPokemonData(data)))
      dispatch(fetchPokemonDescription(pokemonName))
    })
  }
}

middleware

const fetchPromiseMiddleware = store => next => action => {
  if (typeof action.then !== 'function') {
    return next(action)
  }
  return Promise.resolve(action).then(function (res) {
    if (res.status >= 400) {
      throw new Error("Bad response from server")
    }
    return res.json()
  }).then(store.dispatch)
}

I've tried the below but get an error:

store.js:33 Uncaught (in promise) TypeError: (0 , _actionCreators.receivePokemon) is not a function

const fetchPromiseMiddleware = store => next => action => {
  if (typeof action.then !== 'function') {
    return next(action)
  }
  return Promise.resolve(action).then(function (res) {
    if (res.status >= 400) {
      throw new Error("Bad response from server")
    }
    return res.json()
  }).then(function (data) {
    return store.dispatch(receivePokemon(formatPokemonData(data)))
  }).then(function (data) {
    return store.dispatch(fetchPokemonDescription(data.name))
  })
}

Answer 1

您的问题中没有足够的代码，但是似乎当您在显示的代码中调用receivePokemon(formatPokemonData(data))时， receivePokemon不是函数，现在您需要检查定义的位置，可能不是。