Ruby
Add, Remove, Update MIME Header Fields

Demonstrates how to add, remove, or update the content of MIME header fields.
Chilkat Ruby Downloads

Ruby
require 'chilkat'

success = false

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

mime = Chilkat::CkMime.new()

# The contents of this MIME file are shown below, 
# and is also available at https://www.chilkatsoft.com/sampleMime.txt
success = mime.LoadMimeFile("qa_data/mime/sampleMime.txt")
if (success == false)
    print mime.lastErrorText() + "\n";
    exit
end

# The MIME used in this example has the following nested structure
# 
# multipart/alternative
#     text/plain
#     multipart/related
#         text/html
#         image/jpeg
# 

# Adding a top-level MIME header is easy.
mime.AddHeaderField("hello-world","Hello World!")
# If a header field of the same name already exists, the AddHeaderField
# method adds a duplicate.
mime.AddHeaderField("Subject","This is the 2nd Subject header.")
print mime.getEntireHead() + "\n";
print "-" + "\n";

# The top-level header now looks like this:
# 
# 	Subject: Test email.
# 	Content-Type: multipart/alternative; boundary="------------DB171738719FB06D67DEBAA0"
# 	MIME-Version: 1.0
# 	hello-world: Hello World!
# 	Subject: This is the 2nd Subject header.
# 

# The RemoveHeaderField method can remove the 1st occurrance, or all occurrences.
bAllOccurrences = true
# Remove all occurrences of the Subject header;
mime.RemoveHeaderField("Subject",bAllOccurrences)
print mime.getEntireHead() + "\n";
print "-" + "\n";

# After removing all Subject header fields, the top-level header now looks like this:
# 
# Content-Type: multipart/alternative; boundary="------------DB171738719FB06D67DEBAA0"
# MIME-Version: 1.0
# hello-world: Hello World!
# 

# The content of a header field can be updated by calling SetHeaderField.
# If the header field does not already exist, it is added.  Otherwise it is updated.
# Note: The order of header fields SHOULD never matter.
mime.SetHeaderField("hello-world","Goodbye World.")
print mime.getEntireHead() + "\n";
print "-" + "\n";

# Now we have:
# 
# 	Content-Type: multipart/alternative; boundary="------------DB171738719FB06D67DEBAA0"
# 	MIME-Version: 1.0
# 	hello-world: Goodbye World.
# 

# To add/update/delete header fields in sub-parts, navigate to
# the sub-part and do the same..

mpRelated = Chilkat::CkMime.new()
mime.PartAt(1,mpRelated)

pJpg = Chilkat::CkMime.new()
mpRelated.PartAt(1,pJpg)

# Add a header to the image/jpeg sub-header.
pJpg.SetHeaderField("CustomHeader","This is the custom header value.")

# View the entire MIME..
print mime.getMime() + "\n";

# --------------------------------------------------------------
# --------------------------------------------------------------
# The MIME sample file loaded at the beginning of this example
# contains the following MIME:

# Subject: Test email.
# Content-Type: multipart/alternative;
# 	boundary="------------DB171738719FB06D67DEBAA0"
# MIME-Version: 1.0
# 
# --------------DB171738719FB06D67DEBAA0
# Content-Type: text/plain; charset="utf-8"; format=flowed
# Content-Transfer-Encoding: 7bit
# 
# This is a test.
# 
# --------------DB171738719FB06D67DEBAA0
# Content-Type: multipart/related;
# 	boundary="------------A940F1230E6F0105F03DB2CB"
# 
# --------------A940F1230E6F0105F03DB2CB
# Content-Type: text/html; charset="utf-8"
# Content-Transfer-Encoding: 8bit
# 
# <html><head>
# <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
#   </head>
#   <body bgcolor="#FFFFFF" text="#000000">
#     <p>This is a test.&nbsp; <img src="cid:part1.E16AE3B4.1505C436@chilkatsoft.com" height="20" width="20"></p>
#   </body>
# </html>
# 
# --------------A940F1230E6F0105F03DB2CB
# Content-Type: image/jpeg; name="starfish20.jpg"
# Content-Transfer-Encoding: base64
# Content-ID: <part1.E16AE3B4.1505C436@chilkatsoft.com>
# Content-Disposition: inline; filename="starfish20.jpg"
# 
# /9j/4AAQSkZJRgABAQEASABIAAD//gAmRmlsZSB3cml0dGVuIGJ5IEFkb2JlIFBob3Rvc2hvcD8g
# NC4w/9sAQwAQCwwODAoQDg0OEhEQExgoGhgWFhgxIyUdKDozPTw5Mzg3QEhcTkBEV0U3OFBtUVdf
# YmdoZz5NcXlwZHhcZWdj/9sAQwEREhIYFRgvGhovY0I4QmNjY2NjY2NjY2NjY2NjY2NjY2NjY2Nj
# Y2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2Nj/8IAEQgAFAAUAwERAAIRAQMRAf/EABcAAAMBAAAA
# AAAAAAAAAAAAAAIDBAX/xAAYAQADAQEAAAAAAAAAAAAAAAABAgMEAP/aAAwDAQACEAMQAAAB2kZY
# NNEijWKddfTmLgALWH//xAAbEAACAgMBAAAAAAAAAAAAAAABAgMRAAQSE//aAAgBAQABBQL0XqN+
# pM2aqJGMiqFFCyg7z//EABwRAAICAgMAAAAAAAAAAAAAAAERAAIQIQMSUf/aAAgBAwEBPwHqU5aq
# Axx+y1tMQl4elj//xAAcEQEAAQUBAQAAAAAAAAAAAAABEQACEBIhA1H/2gAIAQIBAT8B3Bhqy7Zc
# enyiwmGgDhiOzj//xAAdEAABAwUBAAAAAAAAAAAAAAABAAIREBIhIkFR/9oACAEBAAY/ArZyn+Cg
# xtxWuJaoCnqDuin/xAAcEAABBAMBAAAAAAAAAAAAAAABABEhYRAxQVH/2gAIAQEAAT8hkEwPUUR9
# DYfE4nxtRpIkBTsayuALIiuY/9oADAMBAAIAAwAAABDWPTsf/8QAGhEAAwADAQAAAAAAAAAAAAAA
# AAEREDFBIf/aAAgBAwEBPxC0DVPcWm+Ce4OesrkE6bjH/8QAGBEBAQEBAQAAAAAAAAAAAAAAAREA
# QRD/2gAIAQIBAT8QahMiOc8YgSrnTY3ELclHXn//xAAcEAEBAAIDAQEAAAAAAAAAAAABEQAhMUFx
# EFH/2gAIAQEAAT8Qn3igmSZSj+c4N4zapMy9IjFV98wncN2iuLFsCEbDGxQkI6RO/n//2Q==
# 
# --------------A940F1230E6F0105F03DB2CB--
# 
# --------------DB171738719FB06D67DEBAA0--
#