2009. február 3., kedd

Opening and Closing a CD Tray better


Problem/Question/Abstract:

Opening and Closing a CD Tray?

Answer:

uses
  MMSystem;

// Open CD Tray

{Simple Way:}

mciSendstring('SET CDAUDIO DOOR OPEN WAIT', nil, 0, Self.Handle);

{More complex way:}

function OpenCD(Drive: Char): Boolean;
var
  Res: MciError;
  OpenParm: TMCI_Open_Parms;
  Flags: DWORD;
  S: string;
  DeviceID: Word;
begin
  Result := False;
  S := Drive + ':';
  Flags := MCI_OPEN_TYPE or MCI_OPEN_ELEMENT;
  with OpenParm do
  begin
    dwCallback := 0;
    lpstrDeviceType := 'CDAudio';
    lpstrElementName := PChar(S);
  end;
  Res := mciSendCommand(0, MCI_OPEN, Flags, Longint(@OpenParm));
  if Res <> 0 then
    Exit;
  DeviceID := OpenParm.wDeviceID;
  try
    Res := mciSendCommand(DeviceID, MCI_SET, MCI_SET_DOOR_OPEN, 0);
    if Res = 0 then
      Exit;
    Result := True;
  finally
    mciSendCommand(DeviceID, MCI_CLOSE, Flags, Longint(@OpenParm));
  end;
end;

//Close CD Tray

{Simple Way:}

mciSendstring('SET CDAUDIO DOOR CLOSED WAIT', nil, 0, Self.Handle);

{More complex way:}

function CloseCD(Drive: Char): Boolean;
var
  Res: MciError;
  OpenParm: TMCI_Open_Parms;
  Flags: DWORD;
  S: string;
  DeviceID: Word;
begin
  Result := False;
  S := Drive + ':';
  Flags := MCI_OPEN_TYPE or MCI_OPEN_ELEMENT;
  with OpenParm do
  begin
    dwCallback := 0;
    lpstrDeviceType := 'CDAudio';
    lpstrElementName := PChar(S);
  end;
  Res := mciSendCommand(0, MCI_OPEN, Flags, Longint(@OpenParm));
  if Res <> then
    Exit;
  DeviceID := OpenParm.wDeviceID;
  try
    Res := mciSendCommand(DeviceID, MCI_SET, MCI_SET_DOOR_CLOSED, 0);
    if Res = 0 then
      Exit;
    Result := True;
  finally
    mciSendCommand(DeviceID, MCI_CLOSE, Flags, Longint(@OpenParm));
  end;
end;

Nincsenek megjegyzések:

Megjegyzés küldése