Objective-C

Fetch Full Email Given Email Header

When you fetch email headers using UIDs instead of sequence numbers, the email object (which includes only the header) will have auto-generated ckx-imap-* headers. These headers provide details like the UID and attachments. The IMAP UID is found in the ckx-imap-uid header. Additionally, the ckx-imap-isUid header indicates whether the email header was downloaded by UID, showing YES or NO. Since sequence numbers can change if emails are deleted, UIDs are essential for downloading the correct full email.

The Chilkat Email object offers a GetImapUid method to retrieve the UID from the ckx-imap-uid header. This UID can be used to fetch the full email.

Objective-C

#import <CkoImap.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.

CkoImap *imap = [[CkoImap alloc] init];

//  Connect to an IMAP server.
//  Use TLS
imap.Ssl = YES;
imap.Port = [NSNumber numberWithInt:993];
success = [imap Connect: @"imap.example.com"];
if (success == NO) {
    NSLog(@"%@",imap.LastErrorText);
    return;
}

//  Login
success = [imap Login: @"***" password: @"***"];
if (success == NO) {
    NSLog(@"%@",imap.LastErrorText);
    return;
}

//  Select an IMAP mailbox
success = [imap SelectMailbox: @"Inbox"];
if (success == NO) {
    NSLog(@"%@",imap.LastErrorText);
    return;
}

CkoEmail *emailHeader = [[CkoEmail alloc] init];
CkoEmail *emailFull = [[CkoEmail alloc] init];

int uid = 2014;
BOOL isUid = YES;

//  Fetch only the email header
success = [imap FetchEmail: YES msgId: uid bUid: isUid email: emailHeader];
if (success == NO) {
    NSLog(@"%@",imap.LastErrorText);
    return;
}

//  Now fetch the full email
int uidFromCkxHeader = [emailHeader GetImapUid];
if (uidFromCkxHeader < 0) {
    //  Failed. 
    NSLog(@"%@",@"No ckx-imap-uid header was found.");
    return;
}

success = [imap FetchEmail: NO msgId: uid bUid: isUid email: emailFull];
if (success == NO) {
    NSLog(@"%@",imap.LastErrorText);
    return;
}

//  OK, we have the full email, do whatever we want...

//  Disconnect from the IMAP server.
success = [imap Disconnect];