Java

Attach a File with an Explicit Content Type

Demonstrates the Chilkat Email.AddFileAttachment2 method, which attaches a file from the filesystem and lets you explicitly specify its content type rather than having Chilkat infer it from the file extension. This example attaches a binary file as application/octet-stream.

Background: Extension-based type detection is convenient but not always right — a file may have an unusual or missing extension, or you may need a very specific MIME type for the recipient to process it correctly. Specifying the content type explicitly removes the guesswork. application/octet-stream is the generic "arbitrary binary data" type, a safe default that tells the client to treat the attachment as an opaque download rather than trying to render it.

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import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Email;

public class ChilkatExample {

    public static void main(String[] args) {
        // Demonstrates the AddFileAttachment2 method, which attaches a file and lets you
        // explicitly specify its content type instead of letting Chilkat infer it.

        Email email = new Email();
        email.setSubject("Email with a file attachment");
        email.setBody("Please see the attached file.");

        // Attach a file, explicitly specifying the content type.
        try {
            email.addFileAttachment2("qa_data/attachments/data.bin", "application/octet-stream");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("NumAttachments = " + email.getNumAttachments());

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