Dart Requires Chilkat v11.0.0+

Convert RSA Private Key to Public Key

See more RSA Examples

Demonstrates how to get a public RSA key from a private RSA key. Dart

import 'package:chilkat/chilkat.dart';

void main() {
  final privKey = CkPrivateKey();

  // Step 1: Load the private key from a source.
  // (Chilkat can load private keys from all types of formats, and from in-memory bytes or encoded strings.
  // see the online reference documentation for more options.)
  try {
    privKey.loadPemFile('qa_data/pem/VP_Private.pem');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Step 2: Get the public key object from the private key object.
  final pubKey = CkPublicKey();
  privKey.toPublicKey(pubKey);

  // Step 3: Save the public key in a desired format. 
  // (Chilkat can load or save public and private keys in many different formats.  See
  // the online reference documentation for more options.)

  // Saves to a PKCS8 PEM file.
  final bPreferPkcs1 = false;
  try {
    pubKey.savePemFile(bPreferPkcs1, 'qa_data/pem/VP_Public.pem');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('Extracted and saved public key from private key.');
}