Check if a MIME Entity is Encrypted (S/MIME)

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Demonstrates the Chilkat Mime.IsEncrypted method, which returns whether the entity is a CMS/PKCS #7 encrypted S/MIME wrapper. It takes no arguments.

Note: The file path is relative to the application's current working directory. Absolute paths may also be used. Supply the path to your own file.

Background: This tells you a message is encrypted and must be decrypted before its real content is available — the trigger for supplying a recipient certificate and private key to Decrypt. Reading the body without decrypting first would just yield the opaque PKCS #7 blob.

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bool success = false;

//  Demonstrates the Mime.IsEncrypted method, which returns whether the entity is a CMS/PKCS #7 encrypted S/MIME wrapper.  It takes no arguments.

Chilkat.Mime mime = new Chilkat.Mime();
success = mime.LoadMimeFile("qa_data/encrypted.eml");
if (success == false) {
    Debug.WriteLine(mime.LastErrorText);
    return;
}

if (mime.IsEncrypted()) {
    Debug.WriteLine("This is an encrypted S/MIME message.");
}
else {
    Debug.WriteLine("This is not an encrypted S/MIME message.");
}