Lua

Check if a MIME Part is an Attachment

Demonstrates the Chilkat Mime.IsAttachment method, which returns whether the current part's Content-Disposition is attachment (matched case-insensitively). It takes no arguments.

Note: The file path is relative to the application's current working directory. Absolute paths may also be used. Supply the path to your own file.

Background: Whether a part is an attachment is about disposition, not content type — an image can be inline (Content-Disposition: inline) or an attachment. This predicate keys off that header, which is the right basis for deciding what to list as a downloadable attachment versus what to render within the message body.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the Mime.IsAttachment method, which returns whether the part's Content-Disposition is attachment.  It takes no arguments and applies to the current
-- part.  This example iterates the parts of a multipart message and reports which ones match.

local mime = chilkat.Mime.new()
local success = mime:load_mime_file("qa_data/multipart_message.eml")
if not success then
    print(mime.last_error_text)
    return
end

local n = mime.num_parts
local part = chilkat.Mime.new()
for i = 0, n - 1 do
    success = mime:part_at(i, part)
    if not success then
        print(mime.last_error_text)
        return
    end

    if part:is_attachment() then
        print("Part " .. i .. " (" .. part.content_type .. ") is an attachment.")
    end
end