zoukankan html css js c++ java

react，react-router，redux+react-redux 构建一个React Demo

创建初始化应用

加速我们的npm。

npm install -g cnpm --registry=https://registry.npm.taobao.org

利用create-react-app 创建项目，执行下面创建我们的demo-react应用：

cd ......到你自己的路径
create-react-app reactdemo

我习惯使用VSCode，我用vscode打开这个文件夹，目录结构如下。

安装需要的依赖

我们的项目需要:

react-router:

react-router-dom

redux

react-redux

在VSCode中打开powershell（Ctrl+`）

依次安装

cnpm install react-router --save
cnpm install react-router-dom --save
cnpm install redux --save
cnpm install react-redux --save

打开package.json可以看到我们使用的版本：

不同的版本使用是有一些区别的，尤其路由使用上

创建几个组件页面

在src下创建几个文件夹存放我们使用的组件

在各自文件夹下创建组件js

Login.js

import React,{ Component } from 'react';

//=====组件=====
class Login extends Component {
    
    render() {
        return (
            <div>
                <h3>登录页面</h3>
                <div>
                    用户名<input type="text" />
                </div>
                <div>
                    密码<input type="text" />
                </div>
                <div>
                    <button onClick={this.goLogin}>登录</button>
                </div>
            </div>
        );
    }    
    goLogin(){
        alert("开始登录")
    }
    
    componentDidMount() {
          console.log("Login渲染完毕")
    }    
}

export default Login

Home.js

import React, { Component } from 'react';

//=====组件=====
class Home extends Component {    
    render() {
        return (
            <div>
                <h3>主页</h3>
            </div>
        );
    }    
    componentDidMount() {
          console.log("Home渲染完毕")
    }
}

export default Home

About.js

import React,{ Component } from 'react';

//=====组件=====
class About extends Component {    
    render() {
        return (
            <div>
                <h3>关于我们</h3>
            </div>
        );
    }
    
    componentDidMount() {
          console.log("About渲染完毕")
    }    
}

export default About

News.js

import React,{ Component } from 'react';

//=====组件=====
class News extends Component {    
    constructor(props) {
        super(props);
        // 设置 initial state
        this.state = {
            list: [
                {id:1,title:"a",con:"caaaaaaaaaaaaaaaa"},
                {id:2,title:"b",con:"cbbbbbbbbbbb"},
                {id:3,title:"c",con:"cccccccccccccc"},
                {id:4,title:"d",con:"cddddddddddddd"},
                {id:5,title:"e",con:"ceeeeeeeeeeee"}
            ]
        };
    }
    
    render() {
        return (
            <div>
                <h3>新闻页面</h3>
                <ul>
                    {
                        this.state.list.map(function(item,i){
                            return <li key={item.id}>
                                <a>{item.title}</a>
                                <span>{item.con}</span>
                            </li>                        
                        })    
                    }
                </ul>
            </div>
        );
    }
    
    componentDidMount() {
          console.log("News渲染完毕")
    }
    
}


export default News

搭载路由

我们把页面创建完毕，修改index.js配置路由：

src/index.js:

 1 import React from 'react';
 2 import ReactDOM from 'react-dom';
 3 import {BrowserRouter as Router} from 'react-router-dom';
 4 import './index.css';
 5 import App from './App';
 6 import * as serviceWorker from './serviceWorker';
 7 
 8 ReactDOM.render(
 9     <Router>
10         <App />
11     </Router>    
12 , document.getElementById('root'));
13 
14 // If you want your app to work offline and load faster, you can change
15 // unregister() to register() below. Note this comes with some pitfalls.
16 // Learn more about service workers: https://bit.ly/CRA-PWA
17 serviceWorker.unregister();

View Code

App.js完成我们路由和页面的使用：

import React from 'react';
import {Route,  Link} from 'react-router-dom';
import './App.css';
import Login from './components/login/Login.js';
import Home from './components/home/Home.js';
import About from './components/about/About.js';
import News from './components/news/News.js';

function App() {
  return (
    <div className="App">      
      <ul>
        <li>
          <Link to="/">登录</Link>
        </li>
        <li>
          <Link to="/Home">主页</Link>
        </li>
        <li>
          <Link to="/About">关于我们</Link>
        </li>
        <li>
          <Link to="/News">新闻页面</Link>
        </li>
      </ul>
      <div>
          <Route exact path="/" component={Login}/>
          <Route exact path="/Home" component={Home}/>
          <Route path="/About" component={About}/>
          <Route path="/News" component={News}/>
      </div>
    </div>
  );
}

export default App;

我们预览页面，就可以看到大概了：

npm run start

使用redux

src目录下创建redux文件：

indexRedux.js（根状态树）我们存放登录状态，默认是未登录：

//reducer
//根状态树）我们存放登录状态，默认是未登录：
var isLogin=false;

function indexRedux(state = isLogin, action) {
    switch (action.type) {
        case "GO_LOGIN":
            //登录
            return true
        case "OUT_LOGIN":
            //退出登录
            return false
        default:
              return state
    }
}

export default indexRedux

rootRedux.js（合并所有状态，对外接口）：

import { combineReducers } from 'redux';

//全局reducer
import isLogin from './indexRedux.js'
//子reducer


//合并reducer
var rootRedux = combineReducers({
    isLogin
})

export default rootRedux

index.js使用redux：

import React from 'react';
import ReactDOM from 'react-dom';
import {BrowserRouter as Router} from 'react-router-dom';
import './index.css';
import App from './App';
import * as serviceWorker from './serviceWorker';

//redux 
import { createStore } from 'redux';
//react-redux（关联react和redux）
import { Provider } from 'react-redux';

//reducers 状态树state和逻辑操作
import rootRedux from './rootRedux.js'

//创建状态树和设置

//生成状态树对象
const store = createStore(rootRedux);
ReactDOM.render(
    <Provider store={store}>
        <Router>
            <App />
        </Router>    
    </Provider>
, document.getElementById('root'));

// If you want your app to work offline and load faster, you can change
// unregister() to register() below. Note this comes with some pitfalls.
// Learn more about service workers: https://bit.ly/CRA-PWA
serviceWorker.unregister();

View Code

我们为news创建reducer，把list放入在reducer中，

NewsRedux.js：

//reducer

var newsinit={
    list:[
        {id:1,title:"a",con:"caaaaaaaaaaaaaaaa"},
        {id:2,title:"b",con:"cbbbbbbbbbbb"},
        {id:3,title:"c",con:"cccccccccccccc"},
        {id:4,title:"d",con:"cddddddddddddd"},
        {id:5,title:"e",con:"ceeeeeeeeeeee"}
    ]
};

function NewsRedux(state = newsinit, action) {
    switch (action.type) {
        case "SORT_REVERSE":
            //倒叙显示
            var arr=state.list;
            var arr2=[];
            for(var i=arr.length-1;i>=0;i--){
                arr2.push(arr[i])
            }
            return Object.assign({},state,{list:arr2})
        default:
              return state
    }
}


export default NewsRedux

News.js移除构造函数的json设置：

import React,{ Component } from 'react';

//=====组件=====
class News extends Component {    
    constructor(props) {
        super(props);        
    }
    
    render() {
        return (
            <div>
                <h3>消息</h3>
                <ul>
                    {
                        this.state.list.map(function(item,i){
                            return <li key={item.id}>
                                <a>{item.title}</a>
                                <span>{item.con}</span>
                            </li>                        
                        })    
                    }
                </ul>
            </div>
        );
    }
    
    componentDidMount() {
          console.log("News渲染完毕")
    }
    
}


export default News

rootRedux.js引入news的reducer:

import { combineReducers } from 'redux';

//全局reducer
import isLogin from './indexRedux.js'
//子reducer
import NewsRedux from './components/news/NewsRedux.js'

//合并reducer
var rootRedux = combineReducers({
    isLogin,
    NewsRedux,
})

export default rootRedux

View Code

利用react-redux链接react组件和redux

我们先以news的处理作为操作，首先用react-redux封装News.js组件：

创建src/news/NewsReactRedux.js：.

import { connect } from 'react-redux';

//=====引入组件=====
import News from './News.js'


//=====react-redux 封装组件=====

// 哪些 Redux 全局的 state 是我们组件想要通过 props 获取的？
//负责输入逻辑，即将state映射到 UI 组件的参数（props）
function mapStateToProps(state) {
    return {
        list: state.NewsRedux.list
    };
}

// 哪些 action 创建函数是我们想要通过 props 获取的？
//负责输出逻辑，即将用户对 UI 组件的操作映射成 Action。
function mapDispatchToProps(dispatch) {
    return {
        SORTREVERSE:function(){
            dispatch({type:"SORT_REVERSE"})
        }
    };
}

//封装传递state和dispatch
//把redux的状态数据和action全部发射给News组件
var NewsReactRedux = connect(mapStateToProps,mapDispatchToProps)(News);

export default NewsReactRedux

我们把redux的状态数据和action全部发射给News组件，我们在里面使用即可：

News.js

import React,{ Component } from 'react';

//=====组件=====
class News extends Component {    
    constructor(props) {
        super(props);        
    }
    
    render() {
        return (
            <div>
                <h3>消息</h3>
                <ul>
                    {
                        this.props.list.map(function(item,i){
                            return <li key={item.id}>
                                <a>{item.title}</a>
                                <span>{item.con}</span>
                            </li>                        
                        })    
                    }
                </ul>
                <button onClick={this.SORTREVERSE.bind(this)}>倒叙显示</button>
            </div>
        );
    }
    SORTREVERSE(){
        this.props.SORTREVERSE();
    }
    componentDidMount() {
          console.log("News渲染完毕")
    }
    
}


export default News

App.js使用封装后的组件News：

import React from 'react';
import {Route,  Link} from 'react-router-dom';
import './App.css';
import Login from './components/login/Login.js';
import Home from './components/home/Home.js';
import About from './components/about/About.js';
import NewsReactRedux  from './components/news/NewsReactRedux.js';

function App() {
  return (
    <div className="App">      
      <ul>
        <li>
          <Link to="/">登录</Link>
        </li>
        <li>
          <Link to="/Home">主页</Link>
        </li>
        <li>
          <Link to="/About">关于我们</Link>
        </li>
        <li>
          <Link to="/News">消息</Link>
        </li>
      </ul>
      <div>
          <Route exact path="/" component={Login}/>
          <Route exact path="/Home" component={Home}/>
          <Route path="/About" component={About}/>
          <Route path="/News" component={NewsReactRedux}/>
      </div>
    </div>
  );
}

export default App;

View Code

可以运行看看了。

登录处理

“/“地址就是我们的登录页面，我们点击登录跳转就可以了，不过我们会把用户的登录状态存放在indexRedux.js中，我们不把这个状态存如cookie类似的本地，所以我们刷新页面退出即可，我们只是模拟的处理：

如果存放在了cookie我们要如何处理，这时候在进入网站我们可以调用一个方法去获取cookie的登录状态，不管是什么我们都会执行action把redux的登录状态改为这个！

因为Login.js要和redux结合，我们要修改登录状态，我们还要结合router去手动跳转到主页，

LoginReactRedux.js：

import { connect } from 'react-redux';

//=====引入组件=====
import Login from './Login.js'


//=====react-redux 封装组件=====

// 哪些 Redux 全局的 state 是我们组件想要通过 props 获取的？
function mapStateToProps(state) {
    return {}
}

// 哪些 action 创建函数是我们想要通过 props 获取的？
function mapDispatchToProps(dispatch) {
    return {
        GOLOGIN:function(username,password,history){
            console.log("用户名"+username)
            console.log("密码"+password)
            setTimeout(function(){
                dispatch({type:"GO_LOGIN"})
                history.push("/Home")
            },1000)
            
        }
    };
}

//封装传递state和dispatch
var LoginReactRedux = connect(mapStateToProps,mapDispatchToProps)(Login);

export default LoginReactRedux

import React, { Component } from 'react';

//=====组件=====
class Login extends Component {
    
    render() {
        return (
            <div>
                <h3>登录页面</h3>
                <div>
                    用户名<input type="text" ref="username" />
                </div>
                <div>
                    密码<input type="password" ref="password" />
                </div>
                <div>
                    <button onClick={this.goLogin.bind(this)}>登录</button>
                </div>
            </div>
        );
    }    
    goLogin(){
        this.props.GOLOGIN(this.refs.username.value,this.refs.password.value,this.props.history);
    }
    
    componentDidMount() {
          console.log("Login渲染完毕")
    }    
}

export default Login

App.js:

import React from 'react';
import {Route,  Link} from 'react-router-dom';
import './App.css';
import LoginReactRedux from './components/login/LoginReactRedux.js';
import Home from './components/home/Home.js';
import About from './components/about/About.js';
import NewsReactRedux  from './components/news/NewsReactRedux.js';

function App() {
  return (
    <div className="App">      
      <ul>
        <li>
          <Link to="/">登录</Link>
        </li>
        <li>
          <Link to="/Home">主页</Link>
        </li>
        <li>
          <Link to="/About">关于我们</Link>
        </li>
        <li>
          <Link to="/News">消息</Link>
        </li>
      </ul>
      <div>
          <Route exact path="/" component={LoginReactRedux}/>
          <Route exact path="/Home" component={Home}/>
          <Route path="/About" component={About}/>
          <Route path="/News" component={NewsReactRedux}/>
      </div>
    </div>
  );
}

export default App;

退出登录处理

我们在/Home加一个按钮就是退出按钮他和我们的登录处理相反：

HomeReactRedux.js：

import { connect } from 'react-redux';

//=====引入组件=====
import Home from './Home.js'


//=====react-redux 封装组件=====

// 哪些 Redux 全局的 state 是我们组件想要通过 props 获取的？
function mapStateToProps(state) {
    return {}
}

// 哪些 action 创建函数是我们想要通过 props 获取的？
function mapDispatchToProps(dispatch) {
    return {
        OUTLOGIN:function(history){
            dispatch({type:"OUT_LOGIN"})
            history.push("/")
            
        }
    };
}

//封装传递state和dispatch
var HomeReactRedux = connect(mapStateToProps,mapDispatchToProps)(Home);

export default HomeReactRedux

Home.js：

import React, { Component } from 'react';

//=====组件=====

class Home extends Component {
    
    render() {
        return (
            <div>
                <h3>主页</h3>
                <div>
                    <button onClick={this.outLogin.bind(this)}>退出登录</button>
                </div>
            </div>
        );
    }

    outLogin(){
        this.props.OUTLOGIN(this.props.history);
    }
        
    componentDidMount() {
          console.log("Home渲染完毕")
    }    
}

export default Home

记得修改app.js

import React from 'react';
import {Route,  Link} from 'react-router-dom';
import './App.css';
import LoginReactRedux from './components/login/LoginReactRedux.js';
import HomeReactRedux from './components/home/HomeReactRedux.js';
import About from './components/about/About.js';
import NewsReactRedux  from './components/news/NewsReactRedux.js';

function App() {
  return (
    <div className="App">      
      <ul>
        <li>
          <Link to="/">登录</Link>
        </li>
        <li>
          <Link to="/Home">主页</Link>
        </li>
        <li>
          <Link to="/About">关于我们</Link>
        </li>
        <li>
          <Link to="/News">消息</Link>
        </li>
      </ul>      <div>
          <Route exact path="/" component={LoginReactRedux}/>
          <Route exact path="/Home" component={HomeReactRedux}/>
          <Route path="/About" component={About}/>
          <Route path="/News" component={NewsReactRedux}/>
      </div>
    </div>
  );
}

export default App;

权限处理

显示级别

我们的网站在/地址是处在登录页面，这时候我们应该只有登录框，在进入主页之后会看到跳转链接，我们要获取我们的登录状态，还控制一些标签的显示：

我们在App.js存放了我们的导航，我们只需要对这个组件利用react-redux做一次封装，拿到状态，利用style去处理即可：

我们把导航提出到组件，并且react-redux做封装，在App.js使用

Navigation.js：

import React, { Component } from 'react';
import {Route,Link} from 'react-router-dom';

class Nav extends Component {
  render() {
    return (
        <ul style={{display:this.props.isLogin?"block":"none"}}>
            <li style={{display:this.props.isLogin?"none":"block"}}>
                <Link to="/">登录</Link>
            </li>
            <li>
                <Link to="/Home">主页</Link>
            </li>
            <li>
                <Link to="/About">关于我们</Link>
            </li>
            <li>
                <Link to="/News">消息</Link>
            </li>
        </ul>
    );
  }
}

export default Nav;

NavigationReactRedux.js

import { connect } from 'react-redux';

//=====引入组件=====
import Navigation from './Navigation.js'

//=====react-redux 封装组件=====

// 哪些 Redux 全局的 state 是我们组件想要通过 props 获取的？
function mapStateToProps(state) {
    return {
        isLogin:state.isLogin
    }
}

// 哪些 action 创建函数是我们想要通过 props 获取的？
function mapDispatchToProps(dispatch) {
    return {};
}

//封装传递state和dispatch
var NavigationReactRedux = connect(mapStateToProps,mapDispatchToProps)(Navigation);

export default NavigationReactRedux

App.js我们使用封装后导航：

import React from 'react';
import {Route,  Link} from 'react-router-dom';
import './App.css';
import LoginReactRedux from './components/login/LoginReactRedux.js';
import HomeReactRedux from './components/home/HomeReactRedux.js';
import About from './components/about/About.js';
import NewsReactRedux  from './components/news/NewsReactRedux.js';
import NavigationReactRedux from './components/navigation/NavigationReactRedux.js';

function App() {
  return (
    <div className="App">      
      <NavigationReactRedux />
      <div>
          <Route exact path="/" component={LoginReactRedux}/>
          <Route exact path="/Home" component={HomeReactRedux}/>
          <Route path="/About" component={About}/>
          <Route path="/News" component={NewsReactRedux}/>
      </div>
    </div>
  );
}

export default App;

测试一下

逻辑级别

如果用户直接输入地址怎么办？所以我们在路由对应的页面都要加入登录状态的判断，然后处理是留在当前页面还是跳到登录页面：

我们登录后的页面只有三个，我们先对Home做一个处理，其他的类似：

HomeReactRedux.js：

import { connect } from 'react-redux';

//=====引入组件=====
import Home from './Home.js'


//=====react-redux 封装组件=====

// 哪些 Redux 全局的 state 是我们组件想要通过 props 获取的？
function mapStateToProps(state) {
    return {
        isLogin:state.isLogin
    }
}

// 哪些 action 创建函数是我们想要通过 props 获取的？
function mapDispatchToProps(dispatch) {
    return {
        OUTLOGIN:function(history){
            dispatch({type:"OUT_LOGIN"})
            history.push("/")
        }
    };
}

//封装传递state和dispatch
var HomeReactRedux = connect(mapStateToProps,mapDispatchToProps)(Home);

export default HomeReactRedux

Home.js

import React, { Component } from 'react';
import {Redirect} from 'react-router-dom';
//=====组件=====

class Home extends Component {
    
    render() {
        
        if(this.props.isLogin==false){
            return <Redirect to="/" />
        }
        return (
            <div>
                <h3>主页</h3>
                <div>
                    <button onClick={this.outLogin.bind(this)}>退出登录</button>
                </div>
            </div>
        );
    }

    outLogin(){
        this.props.OUTLOGIN(this.props.history);
    }
        
    componentDidMount() {
          console.log("Home渲染完毕")
    }    
}

export default Home

View Code

其他路由页面同理！！！其实也就是News页面，目前我们其它的页面并不需要验证

NewsReactRedux.js

import { connect } from 'react-redux';

//=====引入组件=====
import News from './News.js'


//=====react-redux 封装组件=====

// 哪些 Redux 全局的 state 是我们组件想要通过 props 获取的？
//负责输入逻辑，即将state映射到 UI 组件的参数（props）
function mapStateToProps(state) {
    return {
        isLogin:state.isLogin,
        list: state.NewsRedux.list
    };
}

// 哪些 action 创建函数是我们想要通过 props 获取的？
//负责输出逻辑，即将用户对 UI 组件的操作映射成 Action。
function mapDispatchToProps(dispatch) {
    return {
        SORTREVERSE:function(){
            dispatch({type:"SORT_REVERSE"})
        }
    };
}

//封装传递state和dispatch
//把redux的状态数据和action全部发射给News组件
var NewsReactRedux = connect(mapStateToProps,mapDispatchToProps)(News);

export default NewsReactRedux

View Code

News.js

import React,{ Component } from 'react';
import {Redirect} from 'react-router-dom';

//=====组件=====
class News extends Component {    
    constructor(props) {
        super(props);        
    }
    
    render() {
        if(this.props.isLogin==false){
            return <Redirect to="/" />
        }
        return (
            <div>
                <h3>消息</h3>
                <ul>
                    {
                        this.props.list.map(function(item,i){
                            return <li key={item.id}>
                                <a>{item.title}</a>
                                <span>{item.con}</span>
                            </li>                        
                        })    
                    }
                </ul>
                <button onClick={this.SORTREVERSE.bind(this)}>倒叙显示</button>
            </div>
        );
    }
    SORTREVERSE(){
        this.props.SORTREVERSE();
    }
    componentDidMount() {
          console.log("News渲染完毕")
    }
    
}


export default News

View Code

刷新问题

我们本地存储可以使用cookie还可以使用localstorage,我们刷新应用就获取localstorage对登录状态的设置，然后action即可！

不过不管是cookie还是localstorage如果用户浏览器的安全级别高就完蛋了，我们存放在这个2个里面哪一个都会遇到这个问题。

我们或许可以这样做，在刷新我们就向后台发送一个请求，这个请求会返回用户是否在登录中和返回用户的一些信息，根据状态我们用手动方法跳转链接。

404错误

先创建一个src/components/exception/NotFind.js文件app.js

import React, { Component } from 'react';
//=====组件=====

class NotFind extends Component {
    
    render() {
        
        return (
            <div>
                <h1>404错误</h1>
                <div>
                    找不到对应的网页
                </div>
            </div>
        );
    }
}

export default NotFind

使用router为我们提供的 Switch 组件：

import React from 'react';
import {Route,  Link,Switch} from 'react-router-dom';
import './App.css';
import LoginReactRedux from './components/login/LoginReactRedux.js';
import HomeReactRedux from './components/home/HomeReactRedux.js';
import About from './components/about/About.js';
import NewsReactRedux  from './components/news/NewsReactRedux.js';
import NavigationReactRedux from './components/navigation/NavigationReactRedux.js';
import NotFind from './components/exception/NotFind.js';

function App() {
  return (
    <div className="App">      
      <NavigationReactRedux />
      <div>
        <Switch>
          <Route exact path="/" component={LoginReactRedux}/>
          <Route exact path="/Home" component={HomeReactRedux}/>
          <Route path="/About" component={About}/>
          <Route path="/News" component={NewsReactRedux}/>
          <Route component={NotFind}/>            
                </Switch> 
      </div>
    </div>
  );
}

export default App;

打包

我们执行下面命令：

npm run build

HashRouter方式

在使用BrowserRouter发布的时候会遇到刷新404错误问题。我们需要做一些设置。所以为了省事干脆用HashRouter

index.js:

import React from 'react';
import ReactDOM from 'react-dom';
// import {BrowserRouter as Router} from 'react-router-dom';
import {HashRouter as Router} from 'react-router-dom';
import './index.css';
import App from './App';
import * as serviceWorker from './serviceWorker';

//redux 
import { createStore } from 'redux';
//react-redux（关联react和redux）
import { Provider } from 'react-redux';

//reducers 状态树state和逻辑操作
import rootRedux from './rootRedux.js'

//创建状态树和设置

//生成状态树对象
const store = createStore(rootRedux);
ReactDOM.render(
    <Provider store={store}>
        <Router>
            <App />
        </Router>    
    </Provider>
, document.getElementById('root'));

// If you want your app to work offline and load faster, you can change
// unregister() to register() below. Note this comes with some pitfalls.
// Learn more about service workers: https://bit.ly/CRA-PWA
serviceWorker.unregister();

代码下载

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原文地址：https://www.cnblogs.com/tianyamoon/p/11242708.html