Lua

Get the Value of a MIME Header Field

See more MIME Examples

Demonstrates how to get the value of a MIME header field. If the header field is not in the top-level MIME header, we must first navigate to the correct MIME part. Lua

local chilkat = require("chilkat")

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

local mime = chilkat.Mime.new()

-- The contents of this MIME file are shown below,
-- and is also available at https://www.chilkatsoft.com/sampleMime.txt
local success = mime:load_mime_file("qa_data/mime/sampleMime.txt")
if not success then
    print(mime.last_error_text)
    return
end

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

-- Getting the content of a top-level MIME header is easy.
-- MIME header fields are case insensitive.
print("Subject = " .. mime:get_header_field("subject"))
print("MIME-Version = " .. mime:get_header_field("mime-version"))

-- To get a MIME header in a sub-part, first navigate to it..

local mpRelated = chilkat.Mime.new()
success = mime:part_at(1, mpRelated)
if not success then
    print(mime.last_error_text)
    return
end

local pJpg = chilkat.Mime.new()
success = mpRelated:part_at(1, pJpg)
if not success then
    print(mpRelated.last_error_text)
    return
end

print("JPG Content-ID = " .. pJpg:get_header_field("content-id"))
print("JPG Content-Type = " .. pJpg:get_header_field("content-type"))

-- --------------------------------------------------------------
-- --------------------------------------------------------------
-- 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--
--