[Alexo]

Код:

procedure AddFileMenu(Const FilePrefix : String);
const
  MenuTitle = 'Edit with Prog';
  
var
  Reg : TRegistry;
  Typ : string;

begin
  reg := TRegistry.Create;
  with reg do begin
    RootKey := HKEY_CLASSES_ROOT;
    OpenKey('.' + FilePrefix, True);
    typ := ReadString('');
    if typ = '' then begin
      typ := Fileprefix + 'file';
      WriteString('', typ);
    end;
    CloseKey;
    OpenKey(typ + '\shell\' + MenuTitle + '\command', True);
    WriteString('', ParamStr(0) + ' "%1"');
    CloseKey;
    Free;
  end;
end;