Create S/MIME Encrypted Message in C#

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This C# S/MIME example program shows how to encrypt any file. The contents of the file are loaded into a MIME message as an attachment, and then encrypted to create an x-pkcs7-mime enveloped message.

		// Encrypts any kind of file into an S/MIME encrypted message.
		private void Encrypt_Click(object sender, System.EventArgs e)
		{
			Chilkat.Mime mime = new Chilkat.Mime();
			
			//Any string passed to UnlockComponent begins the 30-day trial
			mime.UnlockComponent("30-day trial");
			mime.SetBodyFromPlainText("This is a message containing a GIF image file.");
			mime.AppendPartFromFile("dude.gif");
			mime.SaveMime("unencrypted.txt");

			// Locate a certificate in the Current User Store (in the registry)
			// There are many different ways of locating and using certificates
			// using Cert, CertStore and CreateCS.
			Chilkat.CreateCS ccs = new Chilkat.CreateCS();
			Chilkat.CertStore certStore = ccs.OpenCurrentUserStore();
			Chilkat.Cert cert = certStore.FindCertForEmail("matt@chilkatsoft.com");

			// Use the certificate for encryption.
			// This creates an x-pkcs7-mime enveloped message.
			mime.Encrypt(cert);
			mime.SaveMime("encrypted.txt");
		}
	}
}

// Relevant keywords: mime type, mime format, mime tool, mime decoder, mime file, mime decode
// mime file, mime protocol, mime rfc, mime header, email mime, mail mime, mime decoding,
// mime attachment, mime reader, mime download, mime converter, mime content type,
// mime message, mime file type, mime html, mime downloads, mime parser, mime pdf, convert mime
// mime encoding, mime version 1.0, mime pic, mime video, mime software, mime viewer,
/*
 *	content-disposition: attachment; filename="smime.p7m"
	content-transfer-encoding: base64
	content-type: application/x-pkcs7-mime;
		name="smime.p7m"
 * 
 * */