Rust

Count the Messages in a multipart/digest Email

Demonstrates the read-only Chilkat Email.NumDigests property, which is the number of message/rfc822 parts contained within a multipart/digest enclosure. If no such enclosure exists, the value is 0. Digest indexes are zero-based; use GetDigestEmail to retrieve an individual bundled message as its own Email object. This example loads a digest email and lists each message's subject.

Background: A multipart/digest is a way to package many separate emails inside one carrier message — historically used by mailing lists to send a single daily "digest" containing all of that day's posts. Each bundled item is a complete message/rfc822 email with its own headers and body. This differs from NumAttachedMessages, which counts nested messages attached to an ordinary email rather than the members of a digest enclosure.

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Rust


// Demonstrates the read-only Email.NumDigests property, which is the number of
// message/rfc822 parts contained within a multipart/digest enclosure.  If there is no
// multipart/digest enclosure, the value is 0.  Digest indexes are zero-based.

let email = chilkat::Email::new();

// Load a multipart/digest email (a single email that bundles many messages).
if email.load_eml("qa_data/eml/digest.eml").is_err() {
    println!("{}", email.last_error_text());
    return;
}

let n = email.num_digests();
println!("NumDigests = {}", n);

// Retrieve each bundled message as its own Email object.
let digest_email = chilkat::Email::new();
for i in 0..n {
    let _ = email.get_digest_email(i, &digest_email).is_ok();
    println!("Digest {} subject: {}", i, digest_email.subject());
}

// Note: Paths such as "qa_data/..." are relative local filesystem paths,
// relative to the current working directory of the running application.