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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Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    //  Demonstrates the AddFileAttachment2 method, which attaches a file and lets you
    //  explicitly specify its content type instead of letting Chilkat infer it.

    CkEmail email = new CkEmail();
    email.put_Subject("Email with a file attachment");
    email.put_Body("Please see the attached file.");

    //  Attach a file, explicitly specifying the content type.
    success = email.AddFileAttachment2("qa_data/attachments/data.bin","application/octet-stream");
    if (success == false) {
        System.out.println(email.lastErrorText());
        return;
        }

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

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