Encrypt MIME for Multiple Recipients

See more MIME Examples

Demonstrates encrypting the current MIME entity for several recipients at once. A certificate is added for each recipient with AddEncryptCert, and EncryptN then produces a single CMS/PKCS #7 message that each recipient can independently decrypt.

The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

import 'package:chilkat/chilkat.dart';

void main() {
  final mime = CkMime();
  try {
    mime.setBodyFromPlainText('This message will be encrypted.');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Add a certificate for each intended recipient.  Every recipient receives an independently
  // wrapped copy of the message key.
  final cert1 = CkCert();
  try {
    cert1.loadFromFile('qa_data/recipient1.cer');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  try {
    mime.addEncryptCert(cert1);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final cert2 = CkCert();
  try {
    cert2.loadFromFile('qa_data/recipient2.cer');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  try {
    mime.addEncryptCert(cert2);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Encrypt for every added recipient at once.
  try {
    mime.encryptN();
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  try {
    mime.saveMime('qa_output/encrypted_multi.eml');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('Message encrypted for multiple recipients.');
}