Dart

Get a Header Attribute of an Attachment

Demonstrates the Chilkat Email.GetAttachmentAttr method, which returns a header-field attribute value from a header field of the Nth attachment. The first argument is the zero-based attachment index, the second names a header field, and the third names an attribute within it. This example reads the filename attribute of the attachment's Content-Disposition header.

Background: A MIME header can have named parameters after its main value, such as Content-Type: text/plain; charset="utf-8"; name="notes.txt". Here charset and name are attributes. GetAttachmentAttr pulls out one named attribute from a chosen header of a specific attachment, sparing you from parsing the raw header string and dealing with quoting or ordering.

Chilkat Dart Downloads

Download Chilkat for Dart

Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // Demonstrates the GetAttachmentAttr method, which returns a header-field attribute value
  // from a header field of the Nth attachment.  The first argument is the zero-based attachment
  // index, the second is the header field name, and the third is the attribute name.

  final email = CkEmail();
  email.subject = 'Attachment header attribute';

  email.addStringAttachment('notes.txt', 'Some notes.');

  // Get the "filename" attribute of the attachment's Content-Disposition header (index 0).
  final fname = email.getAttachmentAttr(0, 'Content-Disposition', 'filename');
  print('Attachment filename attribute: $fname');
}