Lua

Zip an Email's Attachments into One File

Demonstrates the Chilkat Email.ZipAttachments method, which replaces all of an email's attachments with a single Zip file attachment having the specified filename. The original attachments are removed and packed into the Zip. This example adds two attachments and zips them into one.

Background: Bundling multiple attachments into a single .zip keeps a message tidy, compresses the payload, and works around recipients or gateways that limit the number of attachments. Note that the filename here (files.zip) names the attachment inside the message — it is not a path on disk. The reverse operation is UnzipAttachments.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the ZipAttachments method, which replaces all of an email's attachments
-- with a single Zip file attachment having the specified filename.  The original
-- attachments are removed and packed into the Zip.

local email = chilkat.Email.new()
email.subject = "Zip the attachments"

email:add_string_attachment("a.txt", "first attachment")
email:add_string_attachment("b.txt", "second attachment")
print("NumAttachments before = " .. email.num_attachments)

-- Replace all attachments with a single Zip attachment named "files.zip".
local success = email:zip_attachments("files.zip")
if not success then
    print(email.last_error_text)
    return
end

print("NumAttachments after = " .. email.num_attachments)