当我们在文本框中输入pincode时，如何编写一个react代码来显示PIN码中的所有位置？

import React from 'react';

class PincodeDisplay extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      pincode: ''
    };
  }
}

handleInputChange = (event) => {
  this.setState({
    pincode: event.target.value
  });
}

render() {
  return (
    <div>
      <input type="text" value={this.state.pincode} onChange={this.handleInputChange} />
      <ul>
        {this.state.pincode.split('').map((digit, index) => (
          <li key={index}>{digit}</li>
        ))}
      </ul>
    </div>
  );
}

export default PincodeDisplay;