(Unicode C) S/MIME Encrypt .eml without Sending

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#include <C_CkEmailW.h>
#include <C_CkCertW.h>
#include <C_CkStringBuilderW.h>
#include <C_CkMailManW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkEmailW email;
    HCkCertW cert;
    HCkStringBuilderW sbSmime;
    HCkMailManW mailman;

    success = FALSE;

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

    email = CkEmailW_Create();

    success = CkEmailW_LoadEml(email,L"c:/temp/email/unencrypted.eml");
    if (success == FALSE) {
        wprintf(L"%s\n",CkEmailW_lastErrorText(email));
        CkEmailW_Dispose(email);
        return;
    }

    // The email content is encrypted using AES with a 256-bit key, operating in GCM mode, which provides authenticated encryption.
    CkEmailW_putPkcs7CryptAlg(email,L"aes-gcm");
    CkEmailW_putPkcs7KeyLength(email,256);
    CkEmailW_putOaepPadding(email,TRUE);
    CkEmailW_putOaepHash(email,L"sha256");
    CkEmailW_putOaepMgfHash(email,L"sha256");

    cert = CkCertW_Create();
    success = CkCertW_LoadFromFile(cert,L"c/temps/cert/recipient.cer");
    if (success == FALSE) {
        wprintf(L"%s\n",CkCertW_lastErrorText(cert));
        CkEmailW_Dispose(email);
        CkCertW_Dispose(cert);
        return;
    }

    CkEmailW_putSendEncrypted(email,TRUE);
    CkEmailW_SetEncryptCert(email,cert);

    sbSmime = CkStringBuilderW_Create();

    // The mailman object applies the encryption by rendering the email according to the instructions (property settings) provided in the email object.
    // No email is sent.
    mailman = CkMailManW_Create();
    success = CkMailManW_RenderToMimeSb(mailman,email,sbSmime);
    if (success == FALSE) {
        wprintf(L"%s\n",CkMailManW_lastErrorText(mailman));
        CkEmailW_Dispose(email);
        CkCertW_Dispose(cert);
        CkStringBuilderW_Dispose(sbSmime);
        CkMailManW_Dispose(mailman);
        return;
    }

    success = CkStringBuilderW_WriteFile(sbSmime,L"c:/temp/encryptedEmail.eml",L"utf-8",FALSE);
    if (success == FALSE) {
        wprintf(L"%s\n",CkMailManW_lastErrorText(mailman));
        CkEmailW_Dispose(email);
        CkCertW_Dispose(cert);
        CkStringBuilderW_Dispose(sbSmime);
        CkMailManW_Dispose(mailman);
        return;
    }

    wprintf(L"Success!\n");


    CkEmailW_Dispose(email);
    CkCertW_Dispose(cert);
    CkStringBuilderW_Dispose(sbSmime);
    CkMailManW_Dispose(mailman);

    }