(Tcl) The MIME Content-Type Header Field

Explains the ContentType property and the Content-Type header field including the various attributes that may be included.

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load ./chilkat.dll

# Every part in a MIME messsage should include a Content-Type header field.
# The Content-Type indicates the type of content contained in the MIME part.
# For example: text/plain, image/jpeg, application/pdf, application/json, multipart/mixed, etc.

# Multipart content types are those where the MIME part's body is composed of N inner MIME messages,
# separated by a boundary string.
# This is how MIME gets a nested, tree-like structure.  The most common multipart MIME types
# are (for email related MIME) multipart/mixed, multipart/alternative, and multipart/related,
# and for HTTP related MIME, it is multipart/form-data.

set mime [new_CkMime]

# The Content-Type header field can be set or modified in two ways.
# 1) By setting the ContentType, Micalg, Name, Charset, Boundary, or Protocol properties.
#    Setting the ContentType property sets the primary value (such as "text/plain") of the header field.
#    Each of the other properties listed above will replace or add a particular attribute value.

# 2) By setting the entire contents of the ContentType header with the SetHeaderField method.
#    This updates each of the Content-Type related properties.

# For example:
CkMime_put_ContentType $mime "text/plain"
CkMime_put_Charset $mime "utf-8"

# The Content-Type header field contains this:
#     Content-Type: text/plain; charset=utf-8
puts [CkMime_getEntireHead $mime]
puts "-"

CkMime_SetHeaderField $mime "Content-Type" "image/jpeg; name=\"kitty.jpg\""
# The Content-Type header field now contains this:
#     Content-Type: image/jpeg; name="kitty.jpg"
puts [CkMime_getEntireHead $mime]
puts "-"

# Notice how the properties have been updated:
puts "ContentType property: [CkMime_contentType $mime]"
puts "Charset property: [CkMime_charset $mime]"
puts "Name property: [CkMime_name $mime]"
puts "-"

# To change a particular attribute value, set the property.
CkMime_put_Name $mime "doggy.jpg"
puts [CkMime_getEntireHead $mime]
puts "-"

# To remove an attribute value from the Content-Type header,
# set the property to an empty string.
CkMime_put_Name $mime ""
puts [CkMime_getEntireHead $mime]
puts "-"

delete_CkMime $mime