[델파이] PC의 등록된 통신 포트를 찾아보자

//-----------------------------------------------------------
function TRs232.GetPorts(var APorts: TStringList): integer;
var
    KeyHandle: HKEY;

    ErrCode, Index: Integer;
    ValueName, Data: string;
    ValueLen, DataLen, ValueType: DWORD;
    TmpPorts: TStringList;
begin
    Result := 0 ;
    ErrCode := RegOpenKeyEx(
                            HKEY_LOCAL_MACHINE,
                            'HARDWARE\DEVICEMAP\SERIALCOMM',
                            0,
                            KEY_READ,
                            KeyHandle);

    if ErrCode = ERROR_SUCCESS then  //설치된 포트 없음
    begin
        TmpPorts := TStringList.Create() ;
        try
            Index := 0;
            repeat
                ValueLen := 256;
                DataLen := 256;
                SetLength(ValueName, ValueLen);
                SetLength(Data, DataLen);
                ErrCode := RegEnumValue(
                                        KeyHandle,
                                        Index,
                                        PChar(ValueName),
                                        {$IFDEF DELPHI_4_OR_HIGHER}
                                        Cardinal(ValueLen),
                                        {$ELSE}
                                        ValueLen,
                                        {$ENDIF}
                                        nil,
                                        @ValueType,
                                        PByte(PChar(Data)),
                                        @DataLen);

                if ErrCode = ERROR_SUCCESS then
                begin
                    SetLength(Data, DataLen);
                    TmpPorts.Add(Data);
                    Inc(Index);
                end ;
            until (ErrCode <> ERROR_SUCCESS) ;

            TmpPorts.Sort;  //리스트 소트
            Ports.Assign(TmpPorts);
            Result := TmpPorts.Count;
        finally
            RegCloseKey(KeyHandle);
            TmpPorts.Free() ;
        end;
    end
    else
    begin
        Exception.Create('No Insatalled Comport at This System');
    end ;
end;