React Big Calendar 错误：元素类型无效：预期为字符串（对于内置组件）答案

【问题标题】：React Big Calendar Error: Element type is invalid: expected a string (for built-in components)React Big Calendar 错误：元素类型无效：预期为字符串（对于内置组件）
【发布时间】：2019-08-29 09:16:24
【问题描述】：

第一个错误：

元素类型无效：应为字符串（用于内置组件）或类/函数（用于复合组件）但得到：未定义。你可能忘记从定义它的文件中导出您的组件，或者您可能混淆了默认导入和命名导入。

检查App的渲染方法。

第二个错误：

未捕获的类型错误：无法读取属性“momentLocalizer”的未定义

此处代码：https://stackblitz.com/edit/react-bcvdd6

import BigCalendar from 'react-big-calendar';
import { momentLocalizer } from 'react-big-calendar';
import moment from 'moment';
import 'react-big-calendar/lib/css/react-big-calendar.css';
const localizer = momentLocalizer(moment);

class App extends Component {
  constructor() {
    super();
    this.state = {
      events: [{
          id: 0,
          title: 'All Day Event very long title',
          allDay: true,
          start: new Date(2015, 3, 0),
          end: new Date(2015, 3, 1),
        },
        {
          id: 1,
          title: 'Long Event',
          start: new Date(2015, 3, 7),
          end: new Date(2015, 3, 10),
        },

        {
          id: 2,
          title: 'DTS STARTS',
          start: new Date(2016, 2, 13, 0, 0, 0),
          end: new Date(2016, 2, 20, 0, 0, 0),
        },

        {
          id: 3,
          title: 'DTS ENDS',
          start: new Date(2016, 10, 6, 0, 0, 0),
          end: new Date(2016, 10, 13, 0, 0, 0),
        },

        {
          id: 4,
          title: 'Some Event',
          start: new Date(2015, 3, 9, 0, 0, 0),
          end: new Date(2015, 3, 10, 0, 0, 0),
        }
      ]
    };  
  }

  render() {
    return (
      <div>
        <BigCalendar
          localizer={localizer}
            events={this.state.events}
            startAccessor="start"
            endAccessor="end"
          />
        </div>
    );
  }
}

【问题讨论】：

标签： javascript reactjs react-big-calendar

【解决方案1】：

你应该像这样导入：

import { Calendar, momentLocalizer } from 'react-big-calendar';

<Calendar
    localizer={localizer}
    events={this.state.events}
    startAccessor="start"
    endAccessor="end"
  />

【讨论】：

【解决方案2】：

检查文档，我已经用这段代码解决了这个问题：

import React, { Component } from 'react';
import { render } from 'react-dom';
import Hello from './Hello';
import './style.css';
import { Calendar, momentLocalizer } from 'react-big-calendar';
import moment from 'moment';
import 'react-big-calendar/lib/css/react-big-calendar.css';
const localizer = momentLocalizer(moment);

class App extends Component {
  constructor() {
    super();
    this.state = {
      events: [{
          id: 0,
          title: 'All Day Event very long title',
          allDay: true,
          start: new Date(2015, 3, 0),
          end: new Date(2015, 3, 1),
        },
        {
          id: 1,
          title: 'Long Event',
          start: new Date(2015, 3, 7),
          end: new Date(2015, 3, 10),
        },

        {
          id: 2,
          title: 'DTS STARTS',
          start: new Date(2016, 2, 13, 0, 0, 0),
          end: new Date(2016, 2, 20, 0, 0, 0),
        },

        {
          id: 3,
          title: 'DTS ENDS',
          start: new Date(2016, 10, 6, 0, 0, 0),
          end: new Date(2016, 10, 13, 0, 0, 0),
        },

        {
          id: 4,
          title: 'Some Event',
          start: new Date(2015, 3, 9, 0, 0, 0),
          end: new Date(2015, 3, 10, 0, 0, 0),
        }
      ]
    };  
  }

  render() {
    return (
      <div>
        <Calendar
          localizer={localizer}
            events={this.state.events}
            startAccessor="start"
            endAccessor="end"
          />
        </div>
    );
  }
}

render(<App />, document.getElementById('root'));

【讨论】：

【解决方案3】：

你可以试试这个

BigCalendar.setLocalizer(BigCalendar.momentLocalizer(moment));

【讨论】：