Lua

Get the Size of an Attachment

Demonstrates the Chilkat Email.GetAttachmentSize method, which returns the size in bytes of the attachment at a given zero-based index, or -1 if the index does not identify an existing attachment. This example adds an attachment and prints its size.

Background: The size reported is that of the attachment's actual (decoded) data, not its larger Base64-encoded form on the wire. Knowing per-attachment sizes is handy for enforcing limits, showing a size next to each attachment in a UI, or deciding whether to save or skip a large part. The -1 sentinel is how the method signals an out-of-range index rather than a zero-length attachment.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the GetAttachmentSize method, which returns the size in bytes of the
-- attachment at the given zero-based index.  It returns -1 if the index does not identify
-- an existing attachment.

local email = chilkat.Email.new()
email.subject = "Attachment size"

email:add_string_attachment("notes.txt", "Some notes for the attachment.")

-- Get the size in bytes of the first attachment (index 0).
local sz = email:get_attachment_size(0)
print("Attachment 0 size (bytes) = " .. sz)