React Native

Get a Remote FTP File's Size by Name

Demonstrates the Chilkat Ftp2.GetSizeByName method, which returns the size in bytes of a named file in the current remote directory as a 32-bit integer. The only argument is the filename — a name, not a path. It returns -1 when the file is not found or the size cannot be obtained.

Background: This is the direct way to get one file's size when you already know its name, typically via a SIZE command — no full directory listing required. Because the result is 32-bit, it cannot represent files past about 2 GB; use GetSizeStrByName for large files. The argument must be a bare filename in the current directory, so ChangeRemoteDir to the right place first.

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React Native

import { Ftp2 } from '@chilkat/react-native'

async function chilkatExample() {
  // Demonstrates the Ftp2.GetSizeByName method, which returns the size in bytes of a named file in
  // the current remote directory as a 32-bit integer.  The only argument is the filename (a name,
  // not a path).

  const ftp = new Ftp2();

  ftp.hostname = 'ftp.example.com';
  ftp.username = 'myFtpLogin';

  // Normally you would not hard-code the password in source.  You should instead obtain it
  // from an interactive prompt, environment variable, or a secrets vault.
  ftp.password = 'myPassword';

  try {
    await ftp.connectAsync();
  } catch {
    console.log(ftp.lastErrorText);
    return;
  }

  try {
    await ftp.changeRemoteDirAsync('public_html');
  } catch {
    console.log(ftp.lastErrorText);
    return;
  }

  // Returns -1 when the file is not found or the size cannot be obtained.  For files that may
  // exceed 2 GB, use GetSizeStrByName (returns a decimal string).
  const fileSize = await ftp.getSizeByNameAsync('report.pdf');
  if (fileSize < 0) {
    console.log('File not found, or size unavailable.');
    return;
  }

  console.log(`report.pdf is ${fileSize} bytes`);

  try {
    await ftp.disconnectAsync();
  } catch {
    console.log(ftp.lastErrorText);
    return;
  }
}