React Native

Rename Email Attachments After Adding

Demonstrates how to rename email attachments after adding but before sending. React Native

import { Email, MailMan } 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 mailman = new MailMan();

  mailman.smtpHost = 'smtp.my-mail-server.com';
  mailman.smtpUsername = 'MY_SMTP_USERNAME';
  mailman.smtpPassword = 'MY_SMTP_PASSWORD';
  mailman.smtpSsl = true;
  mailman.smtpPort = 465;

  const email = new Email();

  email.subject = 'This is a test';
  email.body = 'This is a test';
  email.from = 'Chilkat Support <support@chilkatsoft.com>';
  email.addTo('Chilkat Admin', 'admin@chilkatsoft.com');
  // To add more recipients, call AddTo, AddCC, or AddBcc once per recipient.

  // Add some attachments.
  // The AddFileAttachment method returns the value of the content-type it chose for the attachment.
  let contentType: string;
  try {
    contentType = email.addFileAttachment('qa_data/jpg/starfish.jpg');
  } catch {
    console.log(email.lastErrorText);
    return;
  }

  try {
    contentType = email.addFileAttachment('qa_data/pdf/fishing.pdf');
  } catch {
    console.log(email.lastErrorText);
    return;
  }

  // If we save the email to a .eml, we can examine in a text editor.
  try {
    email.saveEml('qa_output/e1.eml');
  } catch {
    console.log(email.lastErrorText);
    console.log('Failed to save .eml');
    return;
  }

  // We see the following in the e1.eml
  // Notice that Chilkat replaced the full path with just the filename.
  // The full local path is not part of the email that gets sent..

  // ...
  // --------------020807050607070004010609
  // Content-Type: image/jpeg; name="starfish.jpg"
  // Content-Transfer-Encoding: base64
  // Content-Disposition: attachment; filename="starfish.jpg"
  // 
  // ...
  // --------------020807050607070004010609
  // Content-Type: application/pdf; name="fishing.pdf"
  // Content-Transfer-Encoding: base64
  // Content-Disposition: attachment; filename="fishing.pdf"
  // ...

  // Before sending, each filename can be changed within the email object.
  // For example:
  email.setAttachmentFilename(0, 'orange_starfish.jpg');
  email.setAttachmentFilename(1, 'tuna_fishing.pdf');

  // Look at the new MIME source of the email in a  text editor...
  try {
    email.saveEml('qa_output/e2.eml');
  } catch {
    console.log(email.lastErrorText);
    console.log('Failed to save .eml');
    return;
  }

  // You'll see this:

  // ...
  // --------------020807050607070004010609
  // Content-Type: image/jpeg; name="orange_starfish.jpg"
  // Content-Transfer-Encoding: base64
  // Content-Disposition: attachment; filename="orange_starfish.jpg"
  // 
  // ...
  // --------------020807050607070004010609
  // Content-Type: application/pdf; name="tuna_fishing.pdf"
  // Content-Transfer-Encoding: base64
  // Content-Disposition: attachment; filename="tuna_fishing.pdf"
  // ...

  // Send the email with the updated filenames..
  try {
    await mailman.sendEmailAsync(email);
  } catch {
    console.log(mailman.lastErrorText);
    return;
  }

  try {
    await mailman.closeSmtpConnectionAsync();
  } catch {
    console.log('Connection to SMTP server not closed cleanly.');
  }

  console.log('Mail with attachments sent!');
}