如何在react js中获取插入符号的位置？

class MyComponent extends React.Component {
  textInputRef = React.createRef();

  render() {
    return <input ref={this.textInputRef} />;
  }
}

handleButtonClick = () => {
  const inputElement = this.textInputRef.current;
  const caretPosition = inputElement.selectionStart;
  console.log('插入符号位置：', caretPosition);
}

render() {
  return (
    <div>
      <input ref={this.textInputRef} />
      <button onClick={this.handleButtonClick}>获取插入符号位置</button>
    </div>
  );
}