Rust

Attach a File to an Email

Demonstrates the Chilkat Email.AddFileAttachment method, which attaches a file read from the filesystem. It returns the content type Chilkat assigned to the attachment (inferred from the file extension). This example attaches a PDF and prints its detected content type.

Background: Each attachment carries a Content-Type (MIME type) such as application/pdf or image/png that tells the receiving client how to handle it. Chilkat gets this from the file's extension. Because attachment bytes are binary, they are Base64-encoded for transport, which is handled automatically — you simply point AddFileAttachment at a path and the file is read, encoded, and packaged into the message.

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Rust

// Demonstrates the AddFileAttachment method, which attaches a file read from the
// filesystem.  It returns the content type Chilkat assigned to the attachment (based on
// the file extension), or returns failure if the file could not be read.

let email = chilkat::Email::new();
email.set_subject("Email with a file attachment");
email.set_body("Please see the attached file.");

// Attach a file.  The return value is the auto-detected content type.
let Ok(content_type) = email.add_file_attachment("qa_data/attachments/report.pdf") else {
    println!("{}", email.last_error_text());
    return;
};

println!("Attached content type = {}", content_type);
println!("NumAttachments = {}", email.num_attachments());

// Note: The path "qa_data/attachments/report.pdf" is a relative local filesystem path,
// relative to the current working directory of the running application.