Lua

Remove a Header Field from an Email

Demonstrates the Chilkat Email.RemoveHeaderField method, which removes by name all occurrences of a header field. Header-field names are case-insensitive, and every repeated occurrence with the given name is removed. This example adds a custom header, then removes it.

Background: Editing a message sometimes means deleting a header outright — stripping a tracking header, removing an X- flag before forwarding, or clearing a stale field before re-sending. Because a field name can appear more than once (like Received), RemoveHeaderField removes all matching occurrences in one call rather than just the first.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the RemoveHeaderField method, which removes by name all occurrences of a
-- header field.  Header-field names are case-insensitive.

local email = chilkat.Email.new()
email.subject = "Remove header field"
email.from = "alice@example.com"

email:add_header_field("X-Custom-Header", "some value")

-- Use HasHeaderMatching to test for the header's presence.  ("*" matches any value.)
local hasBefore = email:has_header_matching("X-Custom-Header", "*", false)
print("Has X-Custom-Header before: " .. tostring(hasBefore))

-- Remove all occurrences of the header field.
email:remove_header_field("X-Custom-Header")

local hasAfter = email:has_header_matching("X-Custom-Header", "*", false)
print("Has X-Custom-Header after: " .. tostring(hasAfter))