(Objective-C) Iterate MIME Parts of an Email

Demonstrates how to iterate over the MIME sub-parts of an email, and retrieve the content of each MIME sub-part body.

Note: This example requires some new features added to Chilkat v9.5.0.95.

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#import <CkoEmail.h>
#import <CkoStringBuilder.h>
#import <NSString.h>
#import <CkoBinData.h>

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

// See the following Chilkat post to Quickly Understand Email MIME

CkoEmail *email = [[CkoEmail alloc] init];

BOOL success = [email LoadEml: @"qa_data/eml/sample.eml"];
if (success == NO) {
    NSLog(@"%@",@"Failed to load .eml");
    return;
}

CkoStringBuilder *sbContentType = [[CkoStringBuilder alloc] init];
BOOL caseSensitive = NO;

// Get the total number of non-multipart MIME sub-parts.
// (This is a simple way of iterating over all the MIME leaf parts regardless of the MIME tree structure)
BOOL inlineOnly = NO;
BOOL excludeAttachments = NO;
NSString *searchSpec = @"*/*";

int numParts = [[email GetNumPartsOfType: searchSpec inlineOnly: inlineOnly excludeAttachments: excludeAttachments] intValue];
int i = 0;
while (i < numParts) {
    // What is the Content-Type of this MIME part?
    [sbContentType Append: [email GetNthContentType: [NSNumber numberWithInt: i] contentType: searchSpec inlineOnly: inlineOnly excludeAttachments: excludeAttachments]];
    if ([sbContentType StartsWith: @"text/" caseSensitive: caseSensitive] == YES) {
        // Get the text body of this MIME part.
        NSString *textBody = [email GetNthTextPartOfType: [NSNumber numberWithInt: i] contentType: searchSpec inlineOnly: inlineOnly excludeAttachments: excludeAttachments];
        NSLog(@"%@%@",@"Got text body for ",[sbContentType GetAsString]);
    }
    else {
        if ([sbContentType ContentsEqual: @"message/rfc822" caseSensitive: caseSensitive] == YES) {
            // If the Content-Type is message/rfc822, then the MIME body for this part contains a full embedded MIME messages.
            // Your application could load it into a Chilkat email object and recursively process...
            CkoEmail *attachedEmail = [[CkoEmail alloc] init];
            CkoBinData *bdMime = [[CkoBinData alloc] init];
            [email GetNthBinaryPartOfTypeBd: [NSNumber numberWithInt: i] contentType: searchSpec inlineOnly: inlineOnly excludeAttachments: excludeAttachments bd: bdMime];
            [attachedEmail SetFromMimeBd: bdMime];
            // Now your app can recursively process the attachedEmail...
        }
        else {
            // Get the bytes of this MIME body part.
            CkoBinData *bd = [[CkoBinData alloc] init];
            [email GetNthBinaryPartOfTypeBd: [NSNumber numberWithInt: i] contentType: searchSpec inlineOnly: inlineOnly excludeAttachments: excludeAttachments bd: bd];
            NSLog(@"%@%@%@%d",@"Got binary body for ",[sbContentType GetAsString],@" numBytes = ",[bd.NumBytes intValue]);
        }

    }

    [sbContentType Clear];
    i = i + 1;
}