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Delphi DLL

Add S/MIME Signature using PFX

See more MIME Examples

Add a digital signature to a MIME message using the certificate + private key from a PFX file.

Chilkat Delphi DLL Downloads

Delphi DLL
uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Cert, Mime;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
mime: HCkMime;
cert: HCkCert;
pfxFilepath: PWideChar;
pfxPassword: PWideChar;

begin
success := False;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

mime := CkMime_Create();

// Load a PFX file into a certificate object.
cert := CkCert_Create();
pfxFilepath := 'pfxFiles/something.pfx';
pfxPassword := 'secret';
success := CkCert_LoadPfxFile(cert,pfxFilepath,pfxPassword);
if (success = False) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(cert));
    Exit;
  end;

success := CkMime_SetBodyFromPlainText(mime,'This is the plain-text MIME body.');

CkMime_putCharset(mime,'utf-8');
CkMime_putEncoding(mime,'quoted-printable');

// Sign the MIME (adds a PKCS7 detached signature)
success := CkMime_AddDetachedSignature(mime,cert);
if (success = False) then
  begin
    Memo1.Lines.Add(CkMime__lastErrorText(mime));
    Exit;
  end;

// Save the S/MIME to a file.
success := CkMime_SaveMime(mime,'/temp/signedMime.txt');
if (success = False) then
  begin
    Memo1.Lines.Add(CkMime__lastErrorText(mime));
    Exit;
  end;

Memo1.Lines.Add('success!');

CkMime_Dispose(mime);
CkCert_Dispose(cert);

end;