unit Unit1; 

interface 

uses 
  {...,}ComCtrls; 

type 
  TForm1 = class(TForm) 
    Button1: TButton; 
    PrintDialog1: TPrintDialog; 
    RichEdit1: TRichEdit; 
    procedure Button1Click(Sender: TObject); 
   {...} 
  end; 

var 
  Form1: TForm1; 

implementation 

{$R *.DFM} 

procedure TForm1.Button1Click(Sender: TObject); 
begin 
  if PrintDialog1.Execute then 
    Richedit1.Print('Ltp1'); {Ltp1, Lpt2 are printers} 
end; 
end.