S/MIME Signed Message

Create an S/MIME signed (PKCS7) message.

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
mime: CHILKATMIMELib_TLB.IChilkatMime;
success: Integer;
cert: TChilkatCert;

begin
mime := CoChilkatMime.Create();

success := mime.UnlockComponent('Anything for 30-day trial.');
if (success = 0) then
  begin
    ShowMessage(mime.LastErrorText);
    Exit;
  end;

mime.AddHeaderField('Subject','This is a test');
mime.AddHeaderField('Abc','123');

mime.SetBodyFromPlainText('This is the body');

cert := TChilkatCert.Create(Self);
//  Load a certificate that has already been installed (from a .pfx)
//  on the computer:
success := cert.LoadByEmailAddress('thawte@chilkatsoft.com');
if (success = 0) then
  begin
    ShowMessage(cert.LastErrorText);
    Exit;
  end;

//  Convert to a signed message.
success := mime.ConvertToSigned(cert.ControlInterface As CHILKATMIMELib_TLB.IChilkatCert);
if (success = 0) then
  begin
    ShowMessage(mime.LastErrorText);
    Exit;
  end;

//  Display the signed MIME:
Memo1.Lines.Add(mime.GetMime());

Memo1.Lines.Add('----');

//  Unwrap to restore the original MIME.
success := mime.UnwrapSecurity();
if (success = 0) then
  begin
    ShowMessage(mime.LastErrorText);
    Exit;
  end;

//  Display the restored (unsigned) MIME:
Memo1.Lines.Add(mime.GetMime());

end;