【共享单车】—— React后台管理系统开发手记：UI菜单各个组件使用（Andt UI组件）

前言：以下内容基于React全家桶+AntD实战课程的学习实践过程记录。最终成果github地址：https://github.com/66Web/react-antd-manager，欢迎star。

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一、按钮Button

• pages->ui->button.js：对应路由/admin/ui/buttons

import React from 'react';
import {Card, Button, Radio} from 'antd'
import './ui.less'

class Buttons extends React.Component{

  state = {
      loading: true,
      size: 'default'
  }  
   
  handleCloseLoading = () =>{
      this.setState({
          loading: false
      })
  } 

  handleChange = (e) => {
      this.setState({
          size: e.target.value
      })
  }

  render(){
      return(
          <div>
              <Card title="基础按钮" className="card-wrap">
                    <Button type="primary">提交</Button>  
                    <Button>普通</Button>
                    <Button type="dashed">非重要功能</Button>  
                    <Button type="danger">删除</Button>
                    <Button disabled>禁用</Button>             
              </Card>
              <Card title="图形按钮" className="card-wrap">
                    <Button icon="plus">创建</Button>  
                    <Button icon="edit">编辑</Button>
                    <Button icon="delete">删除</Button>  
                    <Button shape="circle" icon="search"></Button>
                    <Button type="primary" icon="search">搜索</Button>
                    <Button type="primary" icon="download">下载</Button>               
              </Card>
              <Card title="Loading按钮" className="card-wrap">
                    <Button type="primary" loading={this.state.loading}>确定</Button>  
                    <Button type="primary" shape="circle" loading={this.state.loading}></Button>
                    <Button loading={this.state.loading} >点击加载</Button>  
                    <Button shape="circle" loading={this.state.loading}></Button>
                    <Button type="primary" onClick={this.handleCloseLoading}>关闭</Button>               
              </Card>
              <Card title="按钮组" style={{marginBottom:10}}>
                    <Button.Group>
                        <Button type="primary" icon="left">返回</Button>
                        <Button type="primary" icon="right">前进</Button>
                    </Button.Group>              
              </Card>
              <Card title="按钮尺寸" className="card-wrap">
                    <Radio.Group size={this.state.size} onChange={this.handleChange}>
                        <Radio value="small">小</Radio>
                        <Radio value="default">中</Radio>
                        <Radio value="large">大</Radio>
                    </Radio.Group>
                    <Button type="primary" size={this.state.size}>Imooc</Button>  
                    <Button size={this.state.size}>Imooc</Button>
                    <Button type="dashed" size={this.state.size}>Imooc</Button>  
                    <Button type="danger" size={this.state.size}>Imooc</Button>               
              </Card>
          </div>
      );
  }
}
export default Buttons;

• Button组件

1. type属性 ：表示按钮类型
2. disable属性：表示禁用按钮
3. icon属性：表示按钮图标样式   icon图标集合
4. shape属性：表示按钮形状（circle表示圆形）
5. loading属性：为{true}表示加载中（此时按钮不能点击）
6. size属性：表示组件大小
7. Button.Group按钮组组件：表示包含的Button组件是一个组

• Card组件

1. title属性用于标注卡片上方标题

• Radio组件

1. 外部需要用Radio.Group组件包裹
2. 通过外部组件对象可以获得内部Radio组件的value值(通过e.target.value)

• 坑：Route页面内容超过屏幕时，会出现滚动条，左侧下方出现空白区
• 解决：ui.less中给main添加overflow:auto; 当渲染页面高度超过当前屏幕时，自动滚动

二、弹框Modal

• pages->ui->modals：对应路由/admin/ui/modals

import React from 'react';
import {Card, Button, Modal} from 'antd'
import './ui.less'

export default class Buttons extends React.Component{
    state = {
       showModal1: false,
       showModal2: false,
       showModal3: false,
       showModal4: false
    }
    handleOpen = (type) => {
        this.setState({
           [type]: true
        }) 
    }
    handleConfirm = (type) => {
        Modal[type]({
            title: '确认？',
            content:'你确认你学会了React了吗？',
            onOk() {
                console.log('ok')
            },
            onCancel() {
                console.log('Cancel')
            }
        })
    }
    render(){
        return (
            <div>
                <Card title="基础模态框" className="card-wrap">
                    <Button type="primary" onClick={() => this.handleOpen('showModal1')}>Open</Button>
                    <Button type="primary" onClick={() => this.handleOpen('showModal2')}>自定义页脚</Button>
                    <Button type="primary" onClick={() => this.handleOpen('showModal3')}>顶部20px页脚</Button>
                    <Button type="primary" onClick={() => this.handleOpen('showModal4')}>水平垂直居中</Button>
                </Card>
                <Card title="信息确认框" className="card-wrap">
                    <Button type="primary" onClick={() => this.handleConfirm('confirm')}>Confirm</Button>
                    <Button type="primary" onClick={() => this.handleConfirm('info')}>Info</Button>
                    <Button type="primary" onClick={() => this.handleConfirm('success')}>Success</Button>
                    <Button type="primary" onClick={() => this.handleConfirm('warning')}>Warning</Button>
                </Card>
                <Modal 
                    title="React" 
                    visible={this.state.showModal1} 
                    onCancel={() => {
                        this.setState({
                            showModal1: false
                        })
                    }}>
                    <p>欢迎使用柳柳版弹框</p>
                </Modal>
                <Modal 
                    title="React" 
                    visible={this.state.showModal2} 
                    okText="好的"
                    cancelText="算了"
                    onCancel={() => {
                        this.setState({
                            showModal2: false
                        })
                    }}>
                    <p>欢迎使用柳柳版弹框</p>
                </Modal>
                <Modal 
                    title="React" 
                    style={{top:20}}
                    visible={this.state.showModal3} 
                    onCancel={() => {
                        this.setState({
                            showModal3: false
                        })
                    }}>
                    <p>欢迎使用柳柳版弹框</p>
                </Modal>
                <Modal 
                    title="React" 
                    wrapClassName="vertical-center-modal"
                    visible={this.state.showModal4} 
                    onCancel={() => {
                        this.setState({
                            showModal4: false
                        })
                    }}>
                    <p>欢迎使用柳柳版弹框</p>
                </Modal>
                
            </div>
        )
    }
}

• Modal组件

1. title属性：作为标题显示
2. visible属性：参数为{true|false}，为true则显示，false则不显示
3. onCancel属性：值为一个函数，执行当点击模态框的×或cancel选项时执行的方法
4. Model内部填写的内容将作为模态框的正文内容

• Model自定义页脚实现方式

1. visible属性：{true}或{false}实现是否显示
2. okText属性：设置OK选项的显示内容
3. cancelText属性：设置Cancel选项显示内容

• Model顶部20px弹框实现方式

1. style属性：值为{{top:20}}设定距顶部20px

• Model水平居中实现方式

1. 利用Model组件的wrapClassName设定样式名称

• React监听事件方法时手动绑定this

1. 除了使用xxx.bind(this)外，直接使用箭头函数定义方法会自动绑定this到当前React实例上

   handleConfirm = (type) => {
           Modal[type]({
               title: '确认？',
               content:'你确认你学会了React了吗？',
               onOk() {
                   console.log('ok')
               },
               onCancel() {
                   console.log('Cancel')
               }
           })
   }　　

• React事件调用方法并传参

1. onClick事件内容若为this.handleConfirm('confirm')表示一开始就会自动调用，无法传参；
2. 当需要传参时，需要将onClick中的内容变为：箭头函数返回代参的调用方法，从而实现点击时执行函数并传参调用方法

   onClick={() => this.handleConfirm('confirm')}

3. 传递的参数如果想作为对象的键时，需要用[]进行包裹，如果没包裹直接放置键的位置则视为变量而报错　　

三、加载中Spin　

　　

• pages->ui->loadings：对应路由/admin/ui/loadings

import React from 'react';
import {Card, Spin, Icon, Alert} from 'antd'
import './ui.less'

export default class Loadings extends React.Component{
    render() {
        const icon = <Icon type="loading" style={{fontSize:24}}/>
        return (
            <div>
                <Card title="Spin用法" className="card-wrap">
                    <Spin size="small"/>
                    <Spin style={{margin:'0 10px'}}/>
                    <Spin size="large"/>
                    <Spin indicator={icon} style={{marginLeft:10}}/>
                </Card>
                <Card title="内容遮罩" className="card-wrap">
                    <Alert 
                        message="React"
                        description="欢迎使用柳柳版信息框"
                        type="info"
                    />
                    <Spin>
                        <Alert 
                            message="React"
                            description="欢迎使用柳柳版警告框"
                            type="warning"
                        />
                    </Spin>
                    <Spin tip="加载中">
                        <Alert 
                            message="React"
                            description="欢迎使用柳柳版警告框"
                            type="warning"
                        />
                    </Spin>
                    <Spin indicator={icon}>
                        <Alert 
                            message="React"
                            description="欢迎使用柳柳版警告框"
                            type="warning"
                        />
                    </Spin>
                </Card>
            </div>
        )
    }
}

• Spin组件

1. indicator属性：加载指定的图标indicator={icon}

   const icon = <Icon type="loading"/>;
   <Spin indicator={icon}/>

2. size属性：设置大小
3. tip属性：当作为包裹元素时，可以自定义描述文案

   tip:"加载中" 
   

4. style={{fontSize:24}}  调整显示图标的大小

• 样式注意

1. style={{marginLeft:10}}，marginLeft:xx ，xx是数字可以省略px
2. 如果是style={{margin:'0 10px'}}，xx 是字符串的情况,则不能省略px

• Alert组件

1. type属性：表示提示的样式，有四种选择 success、info、warning、error
2. message属性：表示提示内容(设置标题信息)
3. description属性：表示提示的辅助性文字介绍(设置具体描述的内容)

• 任意组件蒙板加载效果

1. <Spin>组件内嵌套自闭合组件（如<Alert />）

四、通知提醒Notification　　

　　

• pages->ui->notice.js：对应路由/admin/ui/notification

import React from 'react';
import {Card, Button, notification} from 'antd'
import './ui.less'

export default class Notice extends React.Component{
    openNotification = (type, direction) => {
        if(direction){
           notification.config({
               placement: direction
           })
        }
        notification[type]({
            message:'发工资了',
            description:'上个月考勤22天，迟到12天，实发工资2500，请笑纳'
        })
    }
    render(){
        return (
            <div>
                <Card title="通知提醒" className="card-wrap">
                    <Button type="primary" onClick={() => this.openNotification('success')}>Success</Button>
                    <Button type="primary" onClick={() => this.openNotification('info')}>Info</Button>
                    <Button type="primary" onClick={() => this.openNotification('warning')}>Warning</Button>
                    <Button type="primary" onClick={() => this.openNotification('error')}>Error</Button>
                </Card>
                <Card title="自定义方向位" className="card-wrap">
                    <Button type="primary" onClick={() => this.openNotification('success','topLeft')}>Success</Button>
                    <Button type="primary" onClick={() => this.openNotification('info','topRight')}>Info</Button>
                    <Button type="primary" onClick={() => this.openNotification('warning','bottomLeft')}>Warning</Button>
                    <Button type="primary" onClick={() => this.openNotification('error','bottomRight')}>Error</Button>
                </Card>
            </div>
        )
    }
}

• Notification组件Api

1. notification.success(config)
2. notification.error(config)
3. notification.info(config)
4. notification.warning(config)
5. notification.warn(config)

• Notification组件Config

1. message参数：表示通知提醒标题
2. description参数：表示通知提醒内容
3. placement参数：表示弹出位置（可选）

• Notification全局配置方法

1. notification.config(options)
2. 在调用前提前配置，全局一次生效

    openNotification = (type, direction) => {
           if(direction){
              notification.config({
                  placement: direction
              })
           }
           notification[type]({
               message:'发工资了',
               description:'上个月考勤22天，迟到12天，实发工资2500，请笑纳'
           })
    }　　

五、全局提示框Message　　

• pages->ui->messages：对应路由/admin/ui/messages

import React from 'react';
import {Card, Button, message} from 'antd'
import './ui.less'

export default class Messages extends React.Component{
       showMessage = (type) => {
           message[type]("恭喜你，React课程晋级成功");
       }
       render(){
           return (
               <div>
                   <Card title="全局提示框" className="card-wrap">
                        <Button type="primary" onClick={() => this.showMessage('success')}>Success</Button>
                        <Button type="primary" onClick={() => this.showMessage('info')}>Info</Button>
                        <Button type="primary" onClick={() => this.showMessage('warning')}>Warning</Button>
                        <Button type="primary" onClick={() => this.showMessage('loading')}>Loading</Button>
                   </Card>
               </div>
           )
       }
}

• Message组件Api

1. message.success(content, [duration], onClose)
2. message.error(content, [duration], onClose)
3. message.info(content, [duration], onClose)
4. message.warning(content, [duration], onClose)
5. message.loading(content, [duration], onClose)

• Message组件Config

1. content属性：表示提示内容
2. duration属性：表示自动关闭的延时，单位秒（设为 0 时不自动关闭）
3. onClose方法：关闭时触发的回调函数

　　

六、页签Tab　　

• pages->ui->tabs.js：对应路由/admin/ui/tabs

import React from 'react';
import {Card, Tabs, message, Icon} from 'antd'
import './ui.less'

const TabPane = Tabs.TabPane;

export default class Tab extends React.Component{
    handleCallBack = (key) => {
        message.info("Hi,您选择了页签:"+key)
    }
    componentWillMount(){
        this.newTabIndex = 0;
        const panes = [
            {
                title: 'Tab 1',
                content: '欢迎使用柳柳版页签',
                key: '1'
            },
            {
                title: 'Tab 2',
                content: '欢迎使用柳柳版页签',
                key: '2'
            },
            {
                title: 'Tab 3',
                content: '欢迎使用柳柳版页签',
                key: '3'
            }
        ]
        this.setState({
            panes,
            activeKey: panes[0].key
        })
    }
    onChange = (activeKey) => {
        this.setState({
            activeKey
        })
    }
    //onEdit、add、remove直接从官网复制过来即可
    onEdit = (targetKey, action) => {
        this[action](targetKey);
    }
    add = () => {
        const panes = this.state.panes;
        const activeKey = `newTab${this.newTabIndex++}`;
        panes.push({ title: activeKey, content: 'Content of new Tab', key: activeKey });
        this.setState({ panes, activeKey });
    }
    //activeKey:当前激活的key, targetKey:当前删除的Key
    remove = (targetKey) => {
        let activeKey = this.state.activeKey;
        let lastIndex;
        this.state.panes.forEach((pane, i) => {
          if (pane.key === targetKey) {
            lastIndex = i - 1;
          }
        });
        const panes = this.state.panes.filter(pane => pane.key !== targetKey);
        if (lastIndex >= 0 && activeKey === targetKey) {
          activeKey = panes[lastIndex].key;
        }
        this.setState({ panes, activeKey });
    }

    render() {
        return (
            <div>
                <Card title="Tab页签" className="card-wrap">
                    <Tabs defaultActiveKey="1" onChange={this.handleCallBack}>
                       <TabPane tab="Tab 1" key="1">欢迎使用柳柳版页签</TabPane>
                       <TabPane tab="Tab 2" key="2" disabled>欢迎使用柳柳版页签</TabPane>
                       <TabPane tab="Tab 3" key="3">欢迎使用柳柳版页签</TabPane>
                    </Tabs>
                </Card>
                <Card title="Tab带图的页签" className="card-wrap">
                    <Tabs defaultActiveKey="1" onChange={this.handleCallBack}>
                       <TabPane tab={<span><Icon type="plus" />增加</span>} key="1">欢迎使用柳柳版页签</TabPane>
                       <TabPane tab={<span><Icon type="edit" />编辑</span>} key="2">欢迎使用柳柳版页签</TabPane>
                       <TabPane tab={<span><Icon type="delete" />删除</span>} key="3">欢迎使用柳柳版页签</TabPane>
                    </Tabs>
                </Card>
                <Card title="Tab动态的页签" className="card-wrap">
                    <Tabs 
                        onChange={this.onChange}
                        activeKey={this.state.activeKey} 
                        type="editable-card"
                        onEdit={this.onEdit}
                    >
                        {
                            this.state.panes.map((panel) => {
                                return <TabPane 
                                     tab = {panel.title}
                                     key = {panel.key}     
                                >{panel.content}</TabPane>
                            })
                        }
                    </Tabs>
                </Card>
            </div>
        )
    }
}

• Tabs组件

1. type属性：页签的基本样式
2. activeKey属性：当前激活页签的key
3. defaultActiveKey属性：初始化选中面板的 key，如果没有设置 activeKey
4. hideAdd属性：是否隐藏加号图标，在 type="editable-card" 时有效
5. onChange方法：切换面板的回调
6. onEdit方法：新增和删除页签的回调，在 type="editable-card" 时有效

• Tabs.TabPane

1. 页签面板：使用Tabs组件时必须先初始化TabPane

   const TabPane = Tabs.TabPane; 

2. tab属性：选项卡头显示文字

3. key属性：对应activeKey

4. forceRender属性：被隐藏时是否渲染 DOM 结构　　

• Tabs带图页签

1. 指定图标：用Icon组件
2. 注意：JSX语法，{}根对象中不能直接同时套用<Icon />和文字，外层必须包裹一个根元素<span></span>

   tab={<span><Icon type="plus" />增加</span>
   

• Tabs动态页签

1. JS变量循环显示：定义生命周期方法componentWillMount执行 


2. type="editable-card"：指定样式为可编辑的卡片样式

3. onChange事件：设置页签改变时调用方法,设置激活的key

4. onEdit、add、remove方法：直接从官网复制过来即可

七、画廊gallery　　

• pages->ui->gallery：对应路由/admin/ui/gallery

import React from 'react';
import {Card, Row, Col, Modal} from 'antd'
import './ui.less'

export default class Gallery extends React.Component{
    state = {
        visible: false
    }
    openGallery = (imgSrc) => {
        this.setState({
            visible: true,
            currentImg: '/gallery/'+imgSrc
        })
    }
    render(){
        const imgs = [
            ['1.png','2.png','3.png','4.png','5.png'],
            ['6.png','7.png','8.png','9.png','10.png'],
            ['11.png','12.png','13.png','14.png','15.png'],
            ['16.png','17.png','18.png','19.png','20.png'],
            ['21.png','22.png','23.png','24.png','25.png']
        ]
        const imgList = imgs.map((list) => list.map((item) => 
            <Card
               style={{marginBottom:10}}
               cover={<img src={'/gallery/'+item} onClick={() => this.openGallery(item)}/>}
            >
                <Card.Meta 
                    title="React Admin"
                    description="66 Elena gallery"
                />
            </Card>
        ))
        return (
            <div className="card-wrap">
                <Row gutter={10}>
                   <Col md={5}>
                       {imgList[0]}
                   </Col>
                   <Col md={5}>
                       {imgList[1]}
                   </Col> 
                   <Col md={5}>
                       {imgList[2]}
                   </Col> 
                   <Col md={5}>
                       {imgList[3]}
                   </Col> 
                   <Col md={4}>
                       {imgList[4]}
                   </Col>  
                </Row>
                <Modal 
                    width={300}
                    height={500}
                    visible={this.state.visible}
                    title="图片画廊"
                    onCancel={() => {
                        this.setState({
                            visible: false
                        })
                    }}
                    footer={null}
                >
                    {<img src={this.state.currentImg} style={{width:'100%'}}/>}
                </Modal>
            </div>
        )
    }
}

• Card组件

1. cover属性：卡片封面

• Card.Meta

1. 使Card组件支持更灵活的内容：灵活内容
2. title属性：表示标题内容
3. description属性：表示描述内容

• 栅格布局区块间隔

1. 关键：Row 的 gutter 属性，常使用(16+8n)px作为左右间隙（n为自然数）
2. Col 使用样式设置间隙：style={{ marginBottom: 10}}

   <Card
           style={{marginBottom:10}}
           cover={<img src={'/gallery/'+item} onClick={() => this.openGallery(item)}/>}
   >
           <Card.Meta 
                     title="React Admin"
                     description="66 Elena gallery"
            />
   </Card>
   

• 点击查看大图

1. onClick点击事件：使用箭头函数,传递 item

2. 关闭底部按钮：footer={null}

3. 设置Modal宽高：width={300} height={500}

4. 控制Modal显示：设置visible, onCancel　

八、轮播Carousel　　

　　

• pages->ui->carousel：对应路由/admin/ui/carousel

import React from 'react';
import {Card, Carousel} from 'antd'
import './ui.less'

export default class Carousels extends React.Component{
    render(){
        return (
            <div>
                <Card title="文字背景轮播" className="card-wrap">
                    <Carousel autoplay effect="fade">
                        <div><h3>Ant Motion Banner - React</h3></div>
                        <div><h3>Ant Motion Banner - Vue</h3></div>
                        <div><h3>Ant Motion Banner - Angular</h3></div>
                    </Carousel>
                </Card>
                <Card title="图片轮播" className="card-wrap slider-wrap">
                    <Carousel autoplay>
                        <div><img src="/carousel-img/carousel-1.jpg"/></div>
                        <div><img src="/carousel-img/carousel-2.jpg"/></div>
                        <div><img src="/carousel-img/carousel-3.jpg"/></div>
                    </Carousel>
                </Card>
            </div>
        )
    }
}

• Carousel组件

1. vertical属性：表示是否垂直显示
2. dots属性：表示是否显示面板指示点
3. autoplay属性：表示是否自动切换
4. easing属性：表示动态效果
5. effect属性：表示动画效果函数
6. beforeChange：切换面板的回调
7. afterChange：切换面板的回调

• 图片轮播

1. autoplay：设置自动切换
2. effect="fade"：指定淡入淡出动画，不指定默认为scalex动画
3. 轮播组件开始并没有显示：需要引入官网demo的样式或自定义样式

   /* Carousel For demo */
    .ant-carousel .slick-slide {
     text-align: center;
     height: 160px;
     line-height: 160px;
     background: #364d79;
     overflow: hidden;
   }
   
   .ant-carousel .slick-slide h3 {
     color: rgba(246, 250, 33, 0.966);
   }　　

4. 自定义样式：修改图片的默认高度，!important设置优先级

   // 图片轮播
   .slider-wrap .ant-carousel .slick-slide {
     height: 240px!important;
   }　　

九、路由及样式　　

• router.js：配置Admin组件的子路由

import React from 'react'
import {HashRouter, Route, Switch} from 'react-router-dom'
import App from './App'
import Login from './pages/Login'
import NoMatch from './pages/NoMatch'
import Admin from './admin'
import Home from './pages/Home'
import Buttons from './pages/ui/buttons'
import Modals from './pages/ui/modals'
import Loadings from './pages/ui/loadings'
import Notice from './pages/ui/notice'
import Messages from './pages/ui/messages'
import Tabs from './pages/ui/tabs'
import Gallery from './pages/ui/gallery'
import Carousel from './pages/ui/carousel'

export default class IRouter extends React.Component{

    render() {
        return (
           <HashRouter>
               <App>
                  <Route path="/login" component={Login}></Route>
                  <Route path="/admin" render={() => 
                      <Admin>
                          <Switch>
                            <Route path="/admin/home" component={Home}></Route>
                            <Route path="/admin/ui/buttons" component={Buttons}></Route>
                            <Route path="/admin/ui/modals" component={Modals}></Route>
                            <Route path="/admin/ui/loadings" component={Loadings}></Route>
                            <Route path="/admin/ui/notification" component={Notice}></Route>
                            <Route path="/admin/ui/messages" component={Messages}></Route>
                            <Route path="/admin/ui/tabs" component={Tabs}></Route>
                            <Route path="/admin/ui/gallery" component={Gallery}></Route>
                            <Route path="/admin/ui/carousel" component={Carousel}></Route>
                            <Route component={NoMatch}></Route>
                          </Switch>
                      </Admin>
                  }></Route>
                 <Route path="/order/detail" component={Login}></Route>
               </App>
           </HashRouter>
        )
    }
}

• pages->ui->ui.less：设置ui目录下所有组件的样式　　

.card-wrap{
    margin-bottom: 10px;
    button{
        margin-right: 10px;
    }
}
/* modals */
/* use css to set position of modal */
.vertical-center-modal {
    text-align: center;
    white-space: nowrap;
  }
  
  .vertical-center-modal:before {
    content: '';
    display: inline-block;
    height: 100%;
    vertical-align: middle;
    width: 0;
  }
  
  .vertical-center-modal .ant-modal {
    display: inline-block;
    vertical-align: middle;
    top: 0;
    text-align: left;
  }

 /* Carousel For demo */
 .ant-carousel .slick-slide {
  text-align: center;
  height: 160px;
  line-height: 160px;
  background: #364d79;
  overflow: hidden;
}

.ant-carousel .slick-slide h3 {
  color: rgba(246, 250, 33, 0.966);
}

// 图片轮播
.slider-wrap .ant-carousel .slick-slide {
  height: 240px!important;
}

---

注：项目来自慕课网