{ Signing example for Delphi, single pass } 

uses XceedEncryptionLib_TLB
var
  xSign : TXceedSigning; 
  xRSA : DXceedRSASigningMethod; 
  vaBytesRead : OleVariant; 
  vaSignature : OleVariant; 
  vaSeed : OleVariant; 
begin
  xSign := TXceedSigning.Create( self ); 
  xSign.Licenser( 'your license key' ); 

  xRSA := CoXceedRSASigningMethod.Create();  

  try 
    { The following call to SetRandomKeyPair would, in the real world,
      be replaced by the assignment of a Private Key to the  
      PrivateKey property. }  

    vaSeed := varEmpty; 

    xRSA.SetRandomKeyPair( 512, vaSeed ); 
    xSign.SigningMethod := xRSA;  

    vaBytesRead := xSign.ReadFile( 'c:\temp\source.txt', 0, 0, efpSign, true ); 
    vaSignature := xRSA.Get_Signature;  

    { Do something with the Signature... }  

    ShowMessage( 'Signing successful!' );  

    vaBytesRead := xSign.ReadFile( 'c:\temp\source.txt', 0, 0, efpVerify, true ); 

    ShowMessage( 'Data verified successfully' ); 

  except 
    on xErr : Exception do 
      ShowMessage( xErr.Message ); 
  end;  

  xSign.Free; 
end;