javascript - 有用过dva框架么？怎么样？-PHP中文网问答

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redux

actions.js，用setTimeout模拟后端请求

export const REQUEST_TODO = 'REQUEST_TODO';
export const RESPONSE_TODO = 'RESPONSE_TODO';

const request = count => ({type: REQUEST_TODO, payload: {loading: true, count}});

const response = count => ({type: RESPONSE_TODO, payload: {loading: false, count}});

export const fetch = count => {
  return (dispatch) => {
    dispatch(request(count));

    return new Promise(resolve => {
      setTimeout(() => {
        resolve(count + 1);
      }, 1000);
    }).then(data => {
      dispatch(response(data));
    });
  }
};

reducer.js

import { REQUEST_TODO, RESPONSE_TODO } from './actions';

export default (state = {
  loading: false,
  count: 0
}, action) => {
  switch (action.type) {
    case REQUEST_TODO:
      return {...state, ...action.payload};
    case RESPONSE_TODO:
      return {...state, ...action.payload};
    default:
      return state;
  }
};

app.js

import React from 'react';
import { bindActionCreators } from 'redux';
import { connect } from 'react-redux';

import * as actions from './actions';

const App = ({fetch, count, loading}) => {
  return (
    <p>
      {loading ? <p>loading...</p> : <p>{count}</p>}
      <button onClick={() => fetch(count)}>add</button>
    </p>
  )
};

function mapStateToProps(state) {
  return state;
}

function mapDispatchToProps(dispatch) {
  return bindActionCreators(actions, dispatch);
}

export default connect(mapStateToProps, mapDispatchToProps)(App);

main.js

import { render } from 'react-dom';
import { createStore, applyMiddleware } from 'redux';
import { Provider } from 'react-redux'
import thunkMiddleware from 'redux-thunk';

import reducer from './app/reducer';
import App from './app/app';

const store = createStore(reducer, applyMiddleware(thunkMiddleware));

render(
  <Provider store={store}>
    <App/>
  </Provider>
  ,
  document.getElementById('app')
);

使用redux需要拆分action和reducer，实现一个异步流程略繁琐，在看看dva的实现

dva

app.js

import React from 'react'
import { connect } from 'dva';

const App = ({fetch, count, loading}) => {
  return (
    <p>
      {loading ? <p>loading...</p> : <p>{count}</p>}
      <button onClick={() => fetch(count)}>add</button>
    </p>
  )
};


function mapStateToProps(state) {
  return state.demo;
}

function mapDispatchToProps(dispatch) {
  return {
    fetch(count){
      dispatch({type: 'demo/fetch', count});
    }
  }
}

export default connect(mapStateToProps, mapDispatchToProps)(App);

model.js

export default {
  namespace: 'demo',
  state: {
    loading: false,
    count: 0
  },
  reducers: {
    request(state, payload) {
      return {...state, ...payload};
    },
    response(state, payload) {
      return {...state, ...payload};
    }
  },
  effects: {
    *'fetch'(action, {put, call}) {
      yield put({type: 'request', loading: true});

      let count = yield call((count) => {
        return new Promise(resolve => {
          setTimeout(() => {
            resolve(count + 1);
          }, 1000);
        });
      }, action.count);

      yield put({
        type: 'response',
        loading: false,
        count
      });
    }
  }
};

main.js

import dva from 'dva';

import model from './model';
import App from './app';

const app = dva();

app.model(model);

app.router(() => <App />);

app.start('#app');

dva将action和reducer封装到model当中，异步流程采用Generator处理，总体来说简化了不少，虽然我没用过，但是建议楼主可以尝试