react之高阶组件（一）

当两个或多个组件有相同的地方，可以将相同的部分抽离出来

先创建三个组件A、B、C

A.js

 import React, { Component } from 'react'

 class A extends Component {
     render () {
         return (
             <div>
             A组件
             </div>
     )
     }
 }

 export default  A

B.js

import React, { Component } from 'react'

class B extends Component {
    render () {
        return (
            <div>
            B组件
            </div>
    )
    }
}

export default  B

C.js

import React, { Component } from 'react'

class C extends Component {
    render () {
        return (
            <div>
            C组件
            </div>
    )
    }
}

export default  C

然后在app.js中引入

import React, { Component } from 'react';
import A from './components/A'
import C from './components/C'
import B from './components/B'

class App extends Component {
    render() {
        return (
            <div>
                <A />
                <B />
                <C />
            </div>
        );
    }
}

export default App;

认定A组件为相同部分，改写A组件

import React, { Component } from 'react'

function A (WrappedComponent) {
    return class A extends Component
    {
        render () {
            return (
                <div>
                    <div>组件名称</div>
                    <div>
                        <WrappedComponent></WrappedComponent>
                    </div>
                </div>
            )
        }
    }
}

export default A

然后在B、C组件里面引用，改写B、C组件

import React, { Component } from 'react'
import A from './A'

class B extends Component {
    render () {
        return (
            <div>
            B组件
            </div>
    )
    }
}

export default  A( B )

import React, { Component } from 'react'
import A from './A'

class C extends Component {
    render () {
        return (
            <div>
            C组件
            </div>
    )
    }
}

export default  A( C )