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Objective-C

Sending S/MIME Encrypted Email

Sends an encrypted email using the recipient's digital certificate from a .cer file.

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Objective-C
#import <CkoMailMan.h>
#import <CkoCert.h>
#import <CkoEmail.h>

BOOL success = NO;

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

//  The mailman object is used for sending and receiving email.
CkoMailMan *mailman = [[CkoMailMan alloc] init];

//  Set the SMTP server.
mailman.SmtpHost = @"smtp.comcast.net";

//  Load the .cer file into a certificate object.
//  When sending S/MIME encrypted email, it is the recipient's
//  certificate that is used for encryption.  Only the public key
//  is needed to encrypt.  The recipient is the only
//  one possessing the private key, and therefore is the only
//  one able to decrypt.
CkoCert *cert = [[CkoCert alloc] init];
success = [cert LoadFromFile: @"cknotes.cer"];
if (success == NO) {
    NSLog(@"%@",cert.LastErrorText);
    return;
}

//  Create a new email object
CkoEmail *email = [[CkoEmail alloc] init];

email.Subject = @"This email is encrypted";
email.Body = @"This is a digitally encrypted mail";
email.From = @"Chilkat Support <support@chilkatsoft.com>";
success = [email AddTo: @"Chilkat Blog" emailAddress: @"admin@cknotes.com"];

//  Indicate that the email is to be sent encrypted.
email.SendEncrypted = YES;

//  Specify the certificate to be used for encryption.
success = [email SetEncryptCert: cert];

success = [mailman SendEmail: email];
if (success != YES) {
    NSLog(@"%@",mailman.LastErrorText);
}
else {
    NSLog(@"%@",@"Mail Sent!");
}