VB.NET Requires Chilkat v11.0.0+

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. VB.NET

Dim success As Boolean = False

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

Dim mime As New Chilkat.Mime

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.

Dim jpgPart As New Chilkat.Mime
mime.PartAt(1,jpgPart)

jpgPart.Encoding = "binary"

Dim pdfPart As New Chilkat.Mime
mime.PartAt(2,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?
Dim binData As New Chilkat.BinData
'  Write the binary MIME into binData;
mime.GetMimeBd(binData)

Dim email As New Chilkat.Email
'  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","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.
Dim sb As New Chilkat.StringBuilder
email.GetMimeSb(sb)
sb.WriteFile("qa_output/email_fromSb.eml","utf-8",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.GetMimeSb(sb)
sb.WriteFile("qa_output/mime_fromSb.eml","utf-8",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.SaveMime("qa_output/mime_binary.mime")