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Dart

Save a Private Key as a Traditional DER File

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Demonstrates the Chilkat PrivateKey.SavePkcs1File method, which saves the key using the traditional/preferred unencrypted DER representation. The only argument is the destination path.

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 writes the older, algorithm-specific DER structure — useful for compatibility with tools that predate or do not accept PKCS #8. For new work, PKCS #8 (SavePkcs8File) is more interoperable. The output is unencrypted, so protect the file accordingly.

Chilkat Dart Downloads

Dart
import 'package:chilkat/chilkat.dart';

void main() {
  // Load a private key to export.
  final privKey = CkPrivateKey();
  try {
    privKey.loadPemFile('qa_data/private.pem');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Save using the traditional/preferred unencrypted DER representation.
  try {
    privKey.savePkcs1File('qa_output/private_pkcs1.der');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('Saved.');
}