réagir l'entrée du fichier useref

const App = () => {
  const inputRef = useRef(null);
  const [file, setFile] = useState(null);
  return (
    <>
      <input
        ref={inputRef}
        accept=".pdf"
        style={{ display: "none" }}
        id="raised-button-file"
        multiple
        type="file"
        onChange={e => {
          setFile(e.target.files[0]);
        }}
      />
      <label htmlFor="raised-button-file">
        <button component="span">
          <span>file</span>
        </button>
      </label>
    </>
  );
};
Restu Wahyu Saputra