Обработать момент вставки и вытаскивания CD

{ 
  Some applications need to know when the user inserts or 
  removes a compact disc or DVD from a CD-ROM drive without 
  polling for media changes. Windows provide a way to notify these 
  applications through the WM_DEVICECHANGE message. 
}

type
  TForm1 = class(TForm)
  private
    procedure WMDeviceChange(var Msg: TMessage); message WM_DEVICECHANGE;
  public

  end;

{...}

implementation

{$R *.DFM}

procedure TForm1.WMDeviceChange(var Msg: TMessage);
const
  DBT_DEVICEARRIVAL = $8000; // system detected a new device 
  DBT_DEVICEREMOVECOMPLETE = $8004;  // device is gone 
var
   myMsg: string;
begin
  inherited;
  case Msg.wParam of
    DBT_DEVICEARRIVAL: myMsg  := 'CD inserted!';
    DBT_DEVICEREMOVECOMPLETE: myMsg := 'CD removed!';
  end;
  ShowMessage(myMsg);
end;


{*********************************************}

// Advanced Code: 
// When the device is of type volume, then we can get some device specific 
// information, namely specific information about a logical volume. 
// by Juergen Kantz 

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    label1: TLabel;
  private
    procedure WMDeviceChange(var Msg: TMessage); message WM_DeviceChange;
    { Private declarations }
  public
    { Public declarations }
  end;

const
   DBT_DeviceArrival = $8000;
   DBT_DeviceRemoveComplete = $8004;
   DBTF_Media = $0001;
   DBT_DevTyp_Volume = $0002;

 type
   PDevBroadcastHdr = ^TDevBroadcastHdr;
   TDevBroadcastHdr = packed record
     dbcd_size: DWORD;
     dbcd_devicetype: DWORD;
     dbcd_reserved: DWORD;
   end;

 type
   PDevBroadcastVolume = ^TDevBroadcastVolume;
   TDevBroadcastVolume = packed record
     dbcv_size: DWORD;
     dbcv_devicetype: DWORD;
     dbcv_reserved: DWORD;
     dbcv_unitmask: DWORD;
     dbcv_flags: Word;
   end;

 var
   Form1: TForm1;


 implementation

 {$R *.dfm}


 function GetDrive(pDBVol: PDevBroadcastVolume): string;
 var
   i: Byte;
   Maske: DWORD;
 begin
   if (pDBVol^.dbcv_flags and DBTF_Media) = DBTF_Media then
   begin
     Maske := pDBVol^.dbcv_unitmask;
     for i := 0 to 25 do
     begin
       if (Maske and 1) = 1 then
         Result := Char(i + Ord('A')) + ':';
       Maske := Maske shr 1;
     end;
   end;
 end;

 procedure TForm1.WMDeviceChange(var Msg: TMessage);
 var
   Drive: string;
 begin
   case Msg.wParam of
     DBT_DeviceArrival:
       if PDevBroadcastHdr(Msg.lParam)^.dbcd_devicetype = DBT_DevTyp_Volume then
       begin
         Drive := GetDrive(PDevBroadcastVolume(Msg.lParam));
         label1.Caption := 'CD inserted in Drive ' + Drive;
       end;
     DBT_DeviceRemoveComplete:
       if PDevBroadcastHdr(Msg.lParam)^.dbcd_devicetype = DBT_DevTyp_Volume then
       begin
         Drive := GetDrive(PDevBroadcastVolume(Msg.lParam));
         label1.Caption := 'CD removed from Drive ' + Drive;
       end;
   end;
 end;


 end.