Delphi读取本机存在的串口

uses
  Registry;

procedure TForm1.Button1Click(Sender: TObject);
var
  reg : TRegistry;
  sl: TStrings;
  i: integer;
begin
  reg := TRegistry.Create;
  try
    reg.RootKey := HKEY_LOCAL_MACHINE;
    reg.OpenKey('hardware\devicemap\serialcomm', false);
    sl := TStringList.Create;
    try
      reg.GetValueNames(sl);
      for i := 0 to sl.Count -1 do
        Memo1.Lines.Add(reg.ReadString(sl.Strings[i]));
    finally
      sl.Free;
    end;
  finally
    reg.CloseKey;
    reg.free;
  end;
end;