(PureBasic) 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--

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkMime.pb"

Procedure ChilkatExample()

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

    mime.i = CkMime::ckCreate()
    If mime.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

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

    success.i = CkMime::ckLoadMimeFile(mime,"sampleMime2.txt")
    If success = 0
        Debug CkMime::ckLastErrorText(mime)
        CkMime::ckDispose(mime)
        ProcedureReturn
    EndIf

    ; 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.i
    part2 = CkMime::ckGetPart(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.
    filename.s = CkMime::ckGetHeaderFieldAttribute(part2,"Content-Disposition","filename")
    Debug "Filename: " + filename

    ; Because the "filename" is so often accessed, it is also available
    ; by accessing the "Filename" property:
    Debug "Filename: " + CkMime::ckFilename(part2)

    ; The disposition (without attributes) which in this case 
    ; is the string "attachment" is accessed via the Disposition property:
    Debug "Disposition: " + CkMime::ckDisposition(part2)

    ; To get the full value of the Content-Disposition header field,
    ; call GetHeaderField.
    Debug "Content-Disposition: " + CkMime::ckGetHeaderField(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
    name.s = CkMime::ckGetHeaderFieldAttribute(part2,"Content-Type","name")
    Debug "Content-Type name: " + name

    ; Because the "name" is so often accessed, it is also available
    ; by accessing the "Name" property:
    Debug "Content-Type name: " + CkMime::ckName(part2)

    ; The content-type without attributes is available in the
    ; ContentType property:
    Debug "Content-Type: " + CkMime::ckContentType(part2)

    ; To get the full value of the Content-Type header field,
    ; call GetHeaderField.
    Debug "Content-Type: " + CkMime::ckGetHeaderField(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:
    Debug "Content-Transfer-Encoding: " + CkMime::ckEncoding(part2)
    Debug "Content-Transfer-Encoding: " + CkMime::ckGetHeaderField(part2,"Content-Transfer-Encoding")

    CkMime::ckDispose(part2)

    Debug "Finished."


    CkMime::ckDispose(mime)


    ProcedureReturn
EndProcedure