React Native

Determine the Number of Unseen Email Messages

Demonstrates how to determine how many unseen messages exist in an email account on an IMAP server. React Native

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

async function chilkatExample() {
  // This example requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  const imap = new Imap();

  // Connect to an IMAP server.
  // Use TLS
  imap.ssl = true;
  imap.port = 993;
  try {
    await imap.connectAsync('imap.example.com');
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  // Login
  try {
    await imap.loginAsync('***', '***');
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  // Select an IMAP mailbox
  try {
    await imap.selectMailboxAsync('Inbox');
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  // After selecting the mailbox. the total number of emails
  // is immediately available:
  const totalNum = imap.numMessages;
  console.log(`Num messages = ${totalNum}`);

  // To determine the number of unseen messages, a call
  // to Search is required, which returns the set of UIDs
  // of all unseen messages.

  // We can choose to fetch UIDs or sequence numbers.
  const fetchUids = true;
  const messageSet = new MessageSet();
  try {
    await imap.queryMbxAsync('UNSEEN', fetchUids, messageSet);
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  const numUnseen = messageSet.count;
  console.log(numUnseen);

  console.log('UIDs ----');

  // Display the UIDs
  let i = 0;
  while (i < messageSet.count) {
    console.log(messageSet.getId(i));
    i++;
  }

  // Disconnect from the IMAP server.
  await imap.disconnectAsync();
}