Swift
Swift
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.Chilkat Swift Downloads
func chilkatTest() {
var success: Bool = false
// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
let mime = CkoMime()!
mime.setBody(fromPlainText: "This is the plain text body.")
mime.convertToMultipartMixed()
mime.appendPart(fromFile: "qa_data/jpg/penguins.jpg")
mime.appendPart(fromFile: "qa_data/pdf/fishing.pdf")
// At this point, when saved, the MIME bodies will be base64 encoded.
mime.save(path: "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.
let jpgPart = CkoMime()!
mime.part(at: 1, subPart: jpgPart)
jpgPart.encoding = "binary"
let pdfPart = CkoMime()!
mime.part(at: 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.save(path: "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?
let binData = CkoBinData()!
// Write the binary MIME into binData;
mime.getBd(bindat: binData)
let email = CkoEmail()!
// Load the email from the binData.
email.set(fromMimeBd: 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.add(to: "Chilkat", emailAddress: "support@chilkatsoft.com")
email.saveEml(path: "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.
let sb = CkoStringBuilder()!
email.getMimeSb(sb: sb)
sb.writeFile(path: "qa_output/email_fromSb.eml", charset: "utf-8", emitBom: false)
// 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.getSb(sb: sb)
sb.writeFile(path: "qa_output/mime_fromSb.eml", charset: "utf-8", emitBom: false)
// 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.save(path: "qa_output/mime_binary.mime")
}