(Tcl) Parse MIME Header Fields

Demonstrates how to parse MIME header fields, including Content-Type, Content-Disposition, and Content-Transfer-Encoding.

This example uses a MIME test file located at http://www.chilkatsoft.com/testData/sampleMime2.txt. It contains the following MIME:

Content-Type: multipart/mixed;
 boundary="------------080707010302060306060800";

This is a multi-part message in MIME format.

--------------080707010302060306060800
Content-Type: text/plain
Content-Transfer-Encoding: 7bit

This is the plain-text body.
--------------080707010302060306060800
Content-Disposition: attachment; filename="starfish.gif";
Content-Transfer-Encoding: base64
Content-Type: image/gif; name="starfish.gif";

R0lGODlhIAAgAPcAAP///+/v7/f39+/n5/fv7//39/fn597OzufW1tbGxs69vffe3u/W1salpZQQ
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--------------080707010302060306060800--

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load ./chilkat.dll

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

set mime [new_CkMime]

# Load the sampleMime2.txt file into the MIME object.
# (This file is available at http://www.chilkatsoft.com/testData/sampleMime2.txt )

set success [CkMime_LoadMimeFile $mime "sampleMime2.txt"]
if {$success == 0} then {
    puts [CkMime_lastErrorText $mime]
    delete_CkMime $mime
    exit
}

# The GIF image is the 2nd sub-part located directly under the
# top-level MIME node.  Indexing begins at 0, therefore the 2nd
# sub-part is at index 1.
# part2 is a CkMime

set part2 [CkMime_GetPart $mime 1]

# -------------------------------
# Content-Disposition
# -------------------------------
# In this example, the Content-Disposition header field
# contains this value:
# attachment; filename="starfish.gif"

# To get the "filename", call GetHeaderFieldAttribute
# Header field names and attribute names are case insensitive.
set filename [CkMime_getHeaderFieldAttribute $part2 "Content-Disposition" "filename"]
puts "Filename: $filename"

# Because the "filename" is so often accessed, it is also available
# by accessing the "Filename" property:
puts "Filename: [CkMime_filename $part2]"

# The disposition (without attributes) which in this case 
# is the string "attachment" is accessed via the Disposition property:
puts "Disposition: [CkMime_disposition $part2]"

# To get the full value of the Content-Disposition header field,
# call GetHeaderField.
puts "Content-Disposition: [CkMime_getHeaderField $part2 Content-Disposition]"

# -------------------------------
# Content-Type
# -------------------------------
# In this example, the Content-Type header field
# contains this value:
# image/gif; name="starfish.gif"

# To get the "name", call GetHeaderFieldAttribute
set name [CkMime_getHeaderFieldAttribute $part2 "Content-Type" "name"]
puts "Content-Type name: $name"

# Because the "name" is so often accessed, it is also available
# by accessing the "Name" property:
puts "Content-Type name: [CkMime_name $part2]"

# The content-type without attributes is available in the
# ContentType property:
puts "Content-Type: [CkMime_contentType $part2]"

# To get the full value of the Content-Type header field,
# call GetHeaderField.
puts "Content-Type: [CkMime_getHeaderField $part2 Content-Type]"

# -------------------------------
# Content-Transfer-Encoding
# -------------------------------

# The Encoding property contains the value of the
# Content-Transfer-Encoding property. 
# Calling GetHeaderField("Content-Transfer-Encoding") is
# equivalent to accessing the Encoding property:
puts "Content-Transfer-Encoding: [CkMime_encoding $part2]"
puts "Content-Transfer-Encoding: [CkMime_getHeaderField $part2 Content-Transfer-Encoding]"

delete_CkMime $part2

puts "Finished."

delete_CkMime $mime