Reducers和switch语句

时间:2018-01-24 15:48:11

标签: reactjs redux react-redux

我对redux有点新意,我仍然不完全理解type和actionCreator的连接。我在我创建的测试类中有以下代码:

import {GET_AGE_APPROPRIATE_OPTIONS, GET_AGE_OPTIONS, GET_BINDING_TYPE_OPTIONS} from "../actions/options-actions"

export default function(state = [], action){
    switch(action.type){
        case GET_AGE_APPROPRIATE_OPTIONS:
            return action.payload.data;
        case GET_AGE_OPTIONS:
            return action.payload.data;
        case GET_BINDING_TYPE_OPTIONS:
            return action.payload.data;
    }
    return state
}

在我的动作创建者中虽然我有以下代码:

import axios from 'axios';
const ROOT_URL = `http://localhost:8080/`;
const ROOT_OPTIONS_URL = `${ROOT_URL}options`;

export const GET_AGE_OPTIONS = 'GET_AGE_OPTIONS';
export const GET_AGE_APPROPRIATE_OPTIONS = 'GET_AGE_APPROPRIATE_OPTIONS';
export const GET_BINDING_TYPE_OPTIONS = 'GET_BINDING_TYPE_OPTIONS';

export function getAgeOptions() {
    const url = `${ROOT_OPTIONS_URL}/age`;
    const request = axios.get(url);
    return {
        type: GET_AGE_OPTIONS,
        payload: request

    }
}

export function getAgeAppropriateOptions() {
    const url = `${ROOT_OPTIONS_URL}/ageappropriate`;
    const request = axios.get(url);
    return {
        type: GET_AGE_APPROPRIATE_OPTIONS,
        payload: request

    }
}

export function getBindingTypeOptions() {
    const url = `${ROOT_OPTIONS_URL}/bindingtype`;
    const request = axios.get(url);
    return {
        type: GET_BINDING_TYPE_OPTIONS,
        payload: request

    }
}

问题是当我调用其中一个函数时,它只调用reducer的case语句的第一部分。我会想到,因为我的actionCreator传递了不同的类型,它会切换细节。但是在考虑它之后,我无法看到如何在不同的动作上调用reducer,因为我在使用mapDispatchToProps之后直接调用了action。但是这个场景中的mapStateToProps都将调用相同的case语句,因此对mapStateToProps采用相同的值。那么当我调用动作时,如何让reducer调用我需要的类型?我发现让它工作的唯一方法是将所有选项分离到单独的reducer文件中,然后在组合reducers中调用reducer case的正确部分。但它有很多文件,必须在我的combineReducers中调用多个文件。我只是想获得选项,我正在寻找手动组合它的方法。

1 个答案:

答案 0 :(得分:2)

单个减速器可以有多个选项。

const defaultState = {
  ageAppropriateOptions: [],
  ageOptions: [],
  bindingTypeOptions: []
};

export default function(state = defaultState, action){
    switch(action.type){
        case GET_AGE_APPROPRIATE_OPTIONS:
            return {
               ...state,
               ageAppropriateOptions: action.payload.data
            };
        case GET_AGE_OPTIONS:
            return {
                ...state,
                ageOptions: action.payload.data
            };
        case GET_BINDING_TYPE_OPTIONS:
            return {
                ...state,
                bindingTypeOptions: action.payload.data
            };
    }
    return state
}