Dart

Save All MIME Attachments to Files

Demonstrates the Chilkat Mime.PartsToFiles method, which recursively traverses the MIME tree and saves each part having a nonempty filename parameter to a directory. The first argument is the destination directory and the second is a StringTable that receives the saved filenames.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: This extracts every named attachment from a message in one call, walking the whole tree so it finds attachments nested inside multipart containers. It saves only parts that declare a filename — inline body parts without one are skipped — and reports what it wrote via the StringTable, which is handy for logging or follow-up processing. The destination directory must already exist.

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Dart

import 'package:chilkat/chilkat.dart';

void main() {
  final mime = CkMime();
  try {
    mime.loadMimeFile('qa_data/multipart_message.eml');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Recursively traverse the MIME tree and save each part that has a nonempty "filename" parameter
  // to a directory.  The 1st argument is the destination directory and the 2nd is a StringTable
  // that receives the saved filenames.
  final savedFiles = CkStringTable();
  try {
    mime.partsToFiles('qa_output/attachments', savedFiles);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final n = savedFiles.count;
  print('Saved $n files:');
  for (var i = 0; i < n; i++) {
    final String name;
    try {
      name = savedFiles.stringAt(i);
    } on ChilkatException catch (e) {
      print(e.lastErrorText);
      return;
    }

    print(name);
  }
}