Objective-C

Create Binary MIME

See more MIME Examples

Demonstrates how to create and save a multipart/mixed MIME document where the parts (a JPG and a PDF) are NOT base64 encoded, but are instead binary. Objective-C

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

BOOL success = NO;

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

CkoMime *mime = [[CkoMime alloc] init];

[mime SetBodyFromPlainText: @"This is the plain text body."];
[mime ConvertToMultipartMixed];
[mime AppendPartFromFile: @"qa_data/jpg/penguins.jpg"];
[mime AppendPartFromFile: @"qa_data/pdf/fishing.pdf"];

//  At this point, when saved, the MIME bodies will be base64 encoded.
[mime SaveMime: @"qa_output/sample.txt"];

//  We now have the following MIME where everything is base64 encoded:
//  The code that follows shows how to eliminate the base64 to make this binary MIME.

//  	Content-Type: multipart/mixed; boundary="------------000207060703080505060404"
//  
//  	--------------000207060703080505060404
//  	Content-Type: text/plain
//  	Content-Transfer-Encoding: 7bit
//  
//  	This is the plain text body.
//  	--------------000207060703080505060404
//  	Content-Disposition: attachment; filename="penguins.jpg"
//  	Content-Type: image/jpeg; name="penguins.jpg"
//  	Content-Transfer-Encoding: base64
//  
//  	/9j/4AAQSkZJRgABAgEAYABgAAD/7gAOQWRvYmUAZAAAAAAB/+ESCEV4aWYAAE1NACoAAAAIAAcB
//  	MgACAAAAFAAAAGIBOwACAAAABwAAAHZHRgADAAAAAQAEAABHSQADAAAAAQA/AACcnQABAAAADgAA
//  	...
//  	800a1MlLipJHlyU9en7sqVPkBK+gBj+o+1E91Ld7iJk0pJDO5PmDk4FOGOHy6S3JW120W1uCJ5M0
//  	PBa54edOFAc8ePX/2Q==
//  
//  	--------------000207060703080505060404
//  	Content-Disposition: attachment; filename="fishing.pdf"
//  	Content-Type: application/pdf; name="fishing.pdf"
//  	Content-Transfer-Encoding: base64
//  
//  	JVBERi0xLjMKJcfsj6IKNSAwIG9iago8PC9MZW5ndGggNiAwIFIvRmlsdGVyIC9GbGF0ZURlY29k
//  	ZT4+CnN0cmVhbQp4nM1c288cNxVX09A0myq35tom7bSl8E1hp76P/YpASIiXlEg8tDwVKEJfilIe
//  	...
//  	MDRGMT48OTlENkRFQzExQjkzNjA0Mjc1RUFCNzIyMjI4RjA0RjE+XQo+PgpzdGFydHhyZWYKMjk0
//  	MzY5CiUlRU9GCg==
//  
//  	--------------000207060703080505060404--
//  

//  To make it binary MIME (getting rid of the base64), set the Encoding property to "binary"
//  for the JPG and PDF parts.

CkoMime *jpgPart = [[CkoMime alloc] init];
[mime PartAt: [NSNumber numberWithInt: 1] subPart: jpgPart];

jpgPart.Encoding = @"binary";

CkoMime *pdfPart = [[CkoMime alloc] init];
[mime PartAt: [NSNumber numberWithInt: 2] subPart: pdfPart];

pdfPart.Encoding = @"binary";

//  Now save it.  If you try to view this MIME in a text editor,
//  the JPG and PDF parts will be garbled and unintelligible. That's because
//  the bytes do not represent characters.
[mime SaveMime: @"qa_output/sampleBinary.mim"];

//  The MIME now contains this:

//  	Content-Type: multipart/mixed; boundary="------------000207060703080505060404"
//  
//  	--------------000207060703080505060404
//  	Content-Type: text/plain
//  	Content-Transfer-Encoding: 7bit
//  
//  	This is the plain text body.
//  	--------------000207060703080505060404
//  	Content-Disposition: attachment; filename="penguins.jpg"
//  	Content-Type: image/jpeg; name="penguins.jpg"
//  	Content-Transfer-Encoding: binary
//  
//  	<Binary Data Here>
//  
//  	--------------000207060703080505060404
//  	Content-Disposition: attachment; filename="fishing.pdf"
//  	Content-Type: application/pdf; name="fishing.pdf"
//  	Content-Transfer-Encoding: binary
//  
//  	<Binary Data Here>
//  
//  	--------------000207060703080505060404--
//  

//  Can we load this binary MIME into an Email object?
CkoBinData *binData = [[CkoBinData alloc] init];
//  Write the binary MIME into binData;
[mime GetMimeBd: binData];

CkoEmail *email = [[CkoEmail alloc] init];
//  Load the email from the binData.
[email SetFromMimeBd: binData];

//  Note: Many email clients may not be able to correctly process emails
//  using the binary encoding.  Thunderbird has trouble.  Windows Live Mail
//  worked OK.
email.Subject = @"Binary MIME Email";
email.From = @"admin@chilkatsoft.com";
[email AddTo: @"Chilkat" emailAddress: @"support@chilkatsoft.com"];
[email SaveEml: @"qa_output/binaryEmail.eml"];

//  Chilkat does not recommend trying to use binary MIME for email.
//  Binary MIME is typically used in HTTP for uploads and downloads.
//  

//  Also, binary MIME is not representable in a string.  
//  If we try to get the MIME as a string, then it must be encoded
//  using base64.

//  Chilkat automatically changes binary encodings to base64
//  when there's an attempt to get the MIME as a string.
CkoStringBuilder *sb = [[CkoStringBuilder alloc] init];
[email GetMimeSb: sb];
[sb WriteFile: @"qa_output/email_fromSb.eml" charset: @"utf-8" emitBom: NO];

//  Likewise, if we try to get the MIME as a string from the Mime object, 
//  it cannot contain non-character data in a binary encoding.  The binary
//  bytes MUST be in base64.  The act of trying to retrieve the MIME in string
//  format will force Chilkat to convert binary encodings (for non-text parts)
//  to base64.
[mime GetMimeSb: sb];
[sb WriteFile: @"qa_output/mime_fromSb.eml" charset: @"utf-8" emitBom: NO];

//  However, the above use of base64 is just for the purpose of making the MIME
//  string friendly.  If we save the MIME to a file, it's still binary:
[mime SaveMime: @"qa_output/mime_binary.mime"];