Dart

MIME Content-Disposition Header Field

See more MIME Examples

Explains the Content-Disposition header field and the properties used for setting or updating.

Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // The Content-Disposition header field provides a suggestion to the receiver for how the content is to be processed.
  // The standard dispositions are "inline" and "attachment".  

  // A disposition of "attachment" indicates the content is something to be saved to a file and not processed (such as rendering for viewing inline).
  // A disposition of "inline" indicates the content should be processed (displayed) inline with the other parts of the MIME message.

  // For example, an email client could handle a JPG image based on the disposition.  If the disposition is "attachment",
  // the email client (such as Thunderbird, GMail, or Outlook) might simply list the JPG image as one of the email's attachments,
  // but won't display the JPG image.  If the disposition is "inline", the email client might display the JPG image, but not list
  // it as an attachment.

  // The Content-Disposition header field can also include a "filename" attribute.  This is the suggested default filename if the content
  // is to be saved to a file.

  final mime = CkMime();

  // The Content-Disposition header field can be set or modified in two ways.
  // 1) By setting the Disposition and Filename properties.

  // 2) By setting the entire contents of the Content-Disposition header with the SetHeaderField method.
  //    Setting the Content-Disposition header automatically updates the Disposition and Filename properties.

  // For example:
  mime.disposition = 'attachment';
  mime.filename = 'ghost.jpg';

  // The Content-Disposition header field contains this:
  //     Content-Disposition: attachment; filename="ghost.jpg"
  print(mime.getEntireHead());
  print('-');

  // If we set the entire header field..
  mime.setHeaderField('Content-Disposition', 'attachment; filename="zombie.jpg"');
  // The Content-Disposition header field now contains this:
  //     Content-Disposition: attachment; filename="zombie.jpg"
  print(mime.getEntireHead());
  print('-');

  // Notice how the Filename property has been updated
  print('Filename property: ${mime.filename}');
  print('-');

  // To change a particular attribute value, set the property.
  mime.filename = 'skeleton.jpg';
  print(mime.getEntireHead());
  print('-');

  // To remove the filename from the Content-Disposition header,
  // set the property to an empty string.
  mime.filename = '';
  print(mime.getEntireHead());
  print('-');
}