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Dart

Convert ASN.1 to/from Binary DER, XML, and Base64

Demonstrates how to convert ASN.1 from and to any of the following formats: binary DER, Base64, and XML.

Chilkat Dart Downloads

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

void main() {
  final asn = CkAsn();

  // Begin with loading ASN.1 from a binary DER/BER format file.
  try {
    asn.loadBinaryFile('/Users/chilkat/testData/p7b/test.p7b');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Convert ASN.1 to XML:
  final String strXml;
  try {
    strXml = asn.asnToXml();
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // The XML returned by AsnToXml will be compact and not pretty-formatted.
  // Use Chilkat XML to format the XML better:
  final xml = CkXml();
  xml.loadXml(strXml);
  // Assuming success for this example..
  // This is formatted better for human viewing:
  print(xml.getXml());

  // Now get the ASN.1 in base64 format.  Any encoding supported
  // by Chilkat can be passed, such as "hex", "uu", "quoted-printable", "base32", "modbase64", etc.
  final strBase64 = asn.getEncodedDer('base64');

  // Load the ASN.1 from XML:
  final asn2 = CkAsn();
  try {
    asn2.loadAsnXml(xml.getXml());
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Load the ASN.1 from an encoded string, such as base64:
  final asn3 = CkAsn();
  try {
    asn3.loadEncoded(strBase64, 'base64');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }
}