React Native

Fetch an IMAP Message's MIME into a BinData

Demonstrates the Chilkat Imap.FetchSingleBd method, which downloads one message's MIME bytes into a BinData object. If the second argument (bUid) is true, the first argument is a UID; otherwise it is a sequence number. This example downloads message 1's MIME into a BinData and prints the byte count.

Background: This is the binary counterpart to FetchSingleAsMime (which returns a string). A BinData holds raw bytes, so it preserves the message exactly — the right choice when you plan to write the MIME straight to a file, hash it, or hand it to an API expecting a byte buffer, with no charset conversion that could alter binary content.

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React Native

import { BinData, Imap } from '@chilkat/react-native'

async function chilkatExample() {
  // Demonstrates the Imap.FetchSingleBd method, which downloads one message's MIME bytes into a
  // BinData object.  If the 2nd argument (bUid) is true, the 1st argument is a UID; otherwise
  // it is a sequence number.

  const imap = new Imap();

  imap.ssl = true;
  imap.port = 993;

  try {
    await imap.connectAsync('imap.example.com');
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  try {
    await imap.loginAsync('user@example.com', 'myPassword');
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  try {
    await imap.selectMailboxAsync('Inbox');
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  // Download message sequence number 1's MIME bytes into a BinData.  bUid = false.
  const bdMime = new BinData();
  try {
    await imap.fetchSingleBdAsync(1, false, bdMime);
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  console.log(`MIME size (bytes) = ${bdMime.numBytes}`);

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