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Delphi DLL

Send Signed Email using PFX File

Demonstrates how to send a signed email using a digital certificate w/ private key stored in 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, MailMan, Email;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
mailman: HCkMailMan;
email: HCkEmail;

begin
success := False;

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

// The mailman object is used for sending and receiving email.
mailman := CkMailMan_Create();

// Set the SMTP server.
CkMailMan_putSmtpHost(mailman,'smtp.mymailserver.com');

// Create a new email object
email := CkEmail_Create();

CkEmail_putSubject(email,'This email is signed');
CkEmail_putBody(email,'This is a digitally signed mail');
CkEmail_putFrom(email,'Chilkat Admin <admin@chilkatsoft.com>');
success := CkEmail_AddTo(email,'Chilkat Support','support@chilkatsoft.com');

// Indicate that the email should be sent signed.
CkEmail_putSendSigned(email,True);

// Tell the mailman to use a PFX file as a source for locating
// the certificate and private key required for signing.
// The certificate chosen for signing will be the one that
// matches the sender's email address, which also has
// a private key.  All intermediate certs in the chain of 
// authentication, up to and including the root, will
// be included in the signature.
success := CkMailMan_AddPfxSourceFile(mailman,'/pfx_files/chilkatsoft_secret.pfx','secret');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkMailMan__lastErrorText(mailman));
    Exit;
  end;

// Signed email can be sent in two different ways.  
// In a multipart/signed email, the signature is attached as a separate MIME part.
// In an opaque email (signedData) the content of the email is encapsulated within the signature
// and the email is sent as "application/pkcs7-mime". 
// Either should be fine, but some receiving systems might require one or the other..
CkMailMan_putOpaqueSigning(mailman,False);

// Send a signed email.
success := CkMailMan_SendEmail(mailman,email);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkMailMan__lastErrorText(mailman));
  end
else
  begin
    // The LastErrorText property provides information
    // even when successful.
    Memo1.Lines.Add(CkMailMan__lastErrorText(mailman));
    Memo1.Lines.Add('Mail Sent!');
  end;

CkMailMan_Dispose(mailman);
CkEmail_Dispose(email);

end;