(Delphi ActiveX) Load EC Public Key from X,Y Values

Demonstrates how to load an EC public key from X and Y values.

Chilkat for Delphi Downloads Chilkat ActiveX DLL for Delphi Chilkat non-ActiveX DLL for Delphi * The examples here use the ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Integer;
x: WideString;
y: WideString;
json: TChilkatJsonObject;
pubkey: TPublicKey;

begin
// We have the following x and y values in base64 (for an EC point on the P-256 curve).
x := 'Dn7uB1O7kgk74G6qfQwFJESeDnxO6lLjGZFWZJE16tw';
y := 'iOWA5DInzK6nuUGvHJbMVq1Dpj248FqSV2teN3HzmhU';

// Build a JWK that looks like this:

// {
//   "kty": "EC",
//   "crv": "P-256",
//   "x": "Dn7uB1O7kgk74G6qfQwFJESeDnxO6lLjGZFWZJE16tw",
//   "y": "iOWA5DInzK6nuUGvHJbMVq1Dpj248FqSV2teN3HzmhU"
// }

json := TChilkatJsonObject.Create(Self);
json.UpdateString('kty','EC');
json.UpdateString('crv','P-256');
json.UpdateString('x',x);
json.UpdateString('y',y);

// Load from the JWK.
pubkey := TPublicKey.Create(Self);
success := pubkey.LoadFromString(json.Emit());
if (success = 0) then
  begin
    Memo1.Lines.Add(pubkey.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('Success.');
end;