(.NET Core C#) PKCS7 Encrypt using Multiple Certificates

Encrypts MIME using multiple digital certificates. Calls AddEncryptCert once per certificate, followed by a call to EncryptN. The MIME may be decrypted by any owner of one of the certificates + its associated private key.

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// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Mime mime = new Chilkat.Mime();

// Build a simple MIME message to be encrypted:
bool success = mime.AddHeaderField("Content-Type","text/plain");
success = mime.AddHeaderField("abc","123");
mime.SetBody("This is a test");

// A digital certificate is required to create PKCS7 encrypted MIME.
// It can come from a variety of sources: .cer file, .pfx file, PEM files,
// an in-memory representation, or directly from a Windows
// registry-based certificate store.

// Load one cert from a .cer file:
Chilkat.Cert cert1 = new Chilkat.Cert();
success = cert1.LoadFromFile("myCert.cer");
if (success == false) {
    Debug.WriteLine(cert1.LastErrorText);
    return;
}

// Load another cert ...
Chilkat.Cert cert2 = new Chilkat.Cert();
success = cert2.LoadFromFile("anotherCert.cer");
if (success == false) {
    Debug.WriteLine(cert2.LastErrorText);
    return;
}

// Tell the MIME object to use these certs for encrypting:
// (AddEncryptCert shouldn't fail if we already know it contains
// a valid certificate..)
success = mime.AddEncryptCert(cert1);
success = mime.AddEncryptCert(cert2);

// Encrypt the MIME:
success = mime.EncryptN();
if (success == false) {
    Debug.WriteLine(mime.LastErrorText);
    return;
}

// Display the MIME:
Debug.WriteLine(mime.GetMime());

// The resulting S/MIME looks something like this:

// abc: 123
// Content-Disposition: attachment; filename="smime.p7m"
// Content-Transfer-Encoding: base64
// Content-Type: application/x-pkcs7-mime;
//  name="smime.p7m"
// 
// MIID4QYJKoZIhvcNAQcDoIID0jCCA84CAQAxggNlMIIBgQIBADBpMFUxCzAJBgNVBAYTAlpBMSUw
// IwYDVQQKExxUaGF3dGUgQ29uc3VsdGluZyAoUHR5KSBMdGQuMR8wHQYDVQQDExZUaGF3dGUgQ29k
// ZSBTaWduaW5nIENBAhB4ouTcAmLszrGi170k1deSMA0GCSqGSIb3DQEBAQUABIIBAKnOPgmISrNH
// Hd+zESvH5dl5TvBLCxLuIuH6cuZdowHzCqAUzaYFdn1rp88Vvu2x3s6WOvzje/+dE1x0YjEpeqxd
// ufehlb6Jl9ucxSMWARWMxWGxu0eZGJVt+SBBrVddqdtrIU9lVt5rBxkU67P8PxgbwdNCX3qJENRO
// P/rvp5ngoCkpIxeGqSkPvWv+CA3IXS8FPs8Sl4HNPiAj3e9RBm2MxI1u4cn1HvgGg8yHgHLMG5JF
// LzGsmotSQaqEwq2JtOlkjfOwEI+ZhbWQupj6gen2aGc5sW3J26H1usxtV2TQ7WRRxqnZGmlh20dW
// 4lo3kITYI+iapGlJXmrlDYh2CjkwggHcAgEAMIHDMIGuMQswCQYDVQQGEwJVUzELMAkGA1UECBMC
// VVQxFzAVBgNVBAcTDlNhbHQgTGFrZSBDaXR5MR4wHAYDVQQKExVUaGUgVVNFUlRSVVNUIE5ldHdv
// cmsxITAfBgNVBAsTGGh0dHA6Ly93d3cudXNlcnRydXN0LmNvbTE2MDQGA1UEAxMtVVROLVVTRVJG
// aXJzdC1DbGllbnQgQXV0aGVudGljYXRpb24gYW5kIEVtYWlsAhAj50QEWUPwA+jXOiL8sMwXMA0G
// CSqGSIb3DQEBAQUABIIBAFQ1cydWC4M9tdgAlCN03kP8eyuXajwT+5ByhOcJhjuCABg7U8w4Rx28
// braGqV+TCBxjyMsqD0KcW49VT6ZHMpQ1yN8R72qDsidmfm9w3u0jVgsaaBkTJXMy4COY/3cZWmYG
// dL3Qty8uFeQYddytt6UPJpGJZYsrdFG2doe6qHiRtAxxPrd0GmQRcGvxyDdsojkoBlTMbfwaXOI3
// xepR/oh60x/3npUCsl2VpNPfo6oZoej6YZGEuz2MvuWvXVhvuqoTqXGwGDgYMxwTbPwklqZiJtsK
// r5Ep3NlWAQX8MGWL0H+NC22cqJuqUCL05yqyAv+JMCpZGAwOVb/wiVNjpAIwYAYJKoZIhvcNAQcB
// MBkGCCqGSIb3DQMCMA0CAToECA5NAJY12cU+gDgZFUc+nsQUUbiR1GH8iBVLI+XWlja9TXEe1Hzt
// NlsOylRVBDzjNxUtX/zC0YR7bs+2Cf4JbyuMOA==