React 同一组件的多个实例获得相同的状态

jsx
import React from 'react';
// 创建一个上下文对象
const CounterContext = React.createContext();
class Counter extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      count: 0
    };
  }
  // 在父组件的render()方法中提供上下文数据
  render() {
    return (
      
        
          
Counter: {this.state.count}
          Increment
        
      
    );
  }
  // 子组件中通过this.context访问上下文数据
  static contextType = CounterContext;
  increment = () => {
    this.setState(prevState => ({
      count: prevState.count + 1
    }));
  };
}
// 渲染多个Counter组件实例
class App extends React.Component {
  render() {
    return (
      
        
        
        
      
    );
  }
}
export default App;