如何在react原生中使用变量？

class MyComponent extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      myVariable: 'Hello World'
    };
  }

  render() {
    return <div>{this.state.myVariable}</div>;
  }
}

class ParentComponent extends React.Component {
  render() {
    const myVariable = 'Hello World';
    return <ChildComponent myVariable={myVariable} />;
  }
}

class ChildComponent extends React.Component {
  render() {
    return <div>{this.props.myVariable}</div>;
  }
}

const MyContext = React.createContext();

class ParentComponent extends React.Component {
  render() {
    const myVariable = 'Hello World';
    return (
      <MyContext.Provider value={myVariable}>
        <ChildComponent />
      </MyContext.Provider>
    );
  }
}

class ChildComponent extends React.Component {
  static contextType = MyContext;

  render() {
    return <div>{this.context}</div>;
  }
}