Delphi - selecting a serial port

the following code fills the available serial ports into
a combo box named 'SerialCombo'. This code can be
in the Formcreate handler.

var i:integer;

 with TRegistry.create do
  try
   rootkey:=HKEY_LOCAL_MACHINE;
   if keyexists('HARDWARE') then begin
    if openkey('HARDWARE',false)then begin
     if keyexists('DEVICEMAP') then begin
      if openkey('DEVICEMAP',false)then begin
       if keyexists('SERIALCOMM') then begin
        if openkey('SERIALCOMM',false)then begin
         GetValueNames(SerialCombo.items);
         for i:=0 to SerialCombo.items.count-1 do
          begin
           SerialCombo.items[i]:=ReadString(SerialCombo.items[i]);
          end;
         end
        end;
       end;
      end;
     end;
   end;
  finally free;
  end;