Export Digital Certificate's Public Key

The ExportPublicKey method can be called to get a certificate's public key. It can then be saved to any of a number of formats: (1) OpenSSL DER, (2) OpenSSL PEM, (3) RSA DER, (4) XML.

uses
    Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
    Dialogs, StdCtrls,
    CHILKATCERTIFICATELib_TLB,
    OleCtrls;

...

procedure TForm1.Button1Click(Sender: TObject);
var
cert: TChilkatCert;
success: Integer;
pubkey: CHILKATCERTIFICATELib_TLB.IPublicKey;

begin
cert := TChilkatCert.Create(Self);

//  LoadFromFile will load virtually any certificate format file.
//  It will auto-recognize the format and load appropiately.
success := cert.LoadFromFile('/Users/chilkat/testData/cer/chilkat.cer');
if (success <> 1) then
  begin
    Memo1.Lines.Add(cert.LastErrorText);
    Exit;
  end;

//  Get the public key:

pubkey := cert.ExportPublicKey() As CHILKATCERTIFICATELib_TLB.IPublicKey;
if (pubkey = nil ) then
  begin
    Memo1.Lines.Add(cert.LastErrorText);
    Exit;
  end;

//  Save to various formats:
success := pubkey.SaveOpenSslDerFile('/Users/chilkat/testData/pubkeys/chilkat_openSsl.der');
if (success <> 1) then
  begin
    Memo1.Lines.Add(pubkey.LastErrorText);

    Exit;
  end;

success := pubkey.SaveOpenSslPemFile('/Users/chilkat/testData/pubkeys/chilkat_openSsl.pem');
if (success <> 1) then
  begin
    Memo1.Lines.Add(pubkey.LastErrorText);

    Exit;
  end;

success := pubkey.SaveRsaDerFile('/Users/chilkat/testData/pubkeys/chilkat_rsa.der');
if (success <> 1) then
  begin
    Memo1.Lines.Add(pubkey.LastErrorText);

    Exit;
  end;

success := pubkey.SaveXmlFile('/Users/chilkat/testData/pubkeys/chilkat.xml');
if (success <> 1) then
  begin
    Memo1.Lines.Add(pubkey.LastErrorText);

    Exit;
  end;

Memo1.Lines.Add('Public key exported to all file formats.');

end;