如何使用react-native-fs从设备的内存中选择文件？

Question

我想在这里实现的是我已经实现了react-native-smtp-mailer，在其附件中，我如何做到这一点，以便从设备中选择文件并发送电子邮件。

RNSmtpMailer.sendMail({
  mailhost: "smtp.gmail.com",
  port: "465",
  ssl: true,
  username: "usernameEmail",
  password: "password",
  from: "fromEmail",
  recipients: "toEmail1,toEmail2",
  subject: "subject",
  htmlBody: "<h1>header</h1><p>body</p>",
  attachmentPaths: [
    RNFS.ExternalDirectoryPath + "/image.jpg",
    RNFS.DocumentDirectoryPath + "/test.txt",
    RNFS.DocumentDirectoryPath + "/test2.csv",
    RNFS.DocumentDirectoryPath + "/pdfFile.pdf",
    RNFS.DocumentDirectoryPath + "/zipFile.zip",
    RNFS.DocumentDirectoryPath + "/image.png"
  ],
  attachmentNames: [
    "image.jpg",
    "firstFile.txt",
    "secondFile.csv",
    "pdfFile.pdf",
    "zipExample.zip",
    "pngImage.png"
  ]
  attachmentTypes: ["img", "txt", "csv", "pdf", "zip", "img"]
})
  .then(success => console.log(success))
  .catch(err => console.log(err));

我不知道如何选择文件。