Sample code for 30+ languages & platforms
Delphi ActiveX

Find Certificate by Email Address

Locate the certificate containing the specified email address in either the RFC822 Name or the Subject.

Note: This example requires Chilkat v10.1.2 or later.

Chilkat Delphi ActiveX Downloads

Delphi ActiveX
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;
certStore: TChilkatCertStore;
readOnly: Integer;
json: TChilkatJsonObject;
email_address: WideString;
cert: TChilkatCert;

begin
success := 0;

certStore := TChilkatCertStore.Create(Self);

// This opens the Current User certificate store on Windows,
// On MacOS and iOS it opens the default Keychain.
readOnly := 1;
success := certStore.OpenCurrentUserStore(readOnly);
if (success = 0) then
  begin
    Memo1.Lines.Add(certStore.LastErrorText);
    Exit;
  end;

// Locate the certificate containing the specified email address in either the RFC822 Name or the Subject.
json := TChilkatJsonObject.Create(Self);
email_address := 'harold@example.com';
json.UpdateString('email',email_address);

cert := TChilkatCert.Create(Self);
success := certStore.FindCert(json.ControlInterface,cert.ControlInterface);
if (success = 1) then
  begin
    // Show the full distinguished name of the certificate.
    Memo1.Lines.Add('Found: ' + cert.SubjectDN);
  end
else
  begin
    Memo1.Lines.Add('Not found.');
  end;
end;