如何在react-native中将文件从服务器下载到项目代码工作区的特定文件夹？

const RNFS = require('react-native-fs');

const downloadFile = (url, folderPath, fileName) => {
  const downloadDest = `${folderPath}/${fileName}`;

  RNFS.mkdir(folderPath)
    .then(() => {
      RNFS.downloadFile({
        fromUrl: url,
        toFile: downloadDest,
      }).promise
        .then((res) => {
          console.log('File downloaded to:', res.filePath);
        })
        .catch((error) => {
          console.log('Download error:', error);
        });
    })
    .catch((error) => {
      console.log('Folder creation error:', error);
    });
};

// 调用示例
const fileUrl = 'http://example.com/file.pdf';
const folderPath = RNFS.DocumentDirectoryPath + '/Downloads';
const fileName = 'file.pdf';

downloadFile(fileUrl, folderPath, fileName);