mat-选择不显示初始选定项目

import React from 'react';
import { Select, MenuItem } from '@material-ui/core';

const MySelect = () => {
  const [selectedItem, setSelectedItem] = React.useState('');

  const handleChange = (event) => {
    setSelectedItem(event.target.value);
  };

  return (
    <Select value={selectedItem} onChange={handleChange}>
      <MenuItem value="">请选择</MenuItem>
      <MenuItem value="option1">选项1</MenuItem>
      <MenuItem value="option2">选项2</MenuItem>
      <MenuItem value="option3">选项3</MenuItem>
    </Select>
  );
};

export default MySelect;