unit Unit1;    interface    uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls;    type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;    var
  Form1: TForm1;    implementation    {$R *.DFM}
Function GetCDList : String;
Var
   I : Integer;
  Drives: Integer;
  Tmp : String;
begin
  Drives := GetLogicalDrives;
  Result := '';
  For I := 0 To 25 Do // A=0 ¨ì Z=25
    If (((1 Shl I) And Drives)<>0) Then
    Begin
      Tmp := Char(65 I) ':\';
      If (GetDriveType(PChar(Tmp))=DRIVE_CDROM) Then
                                   Result := Result Char(65 I);
    End; 
End;     procedure TForm1.Button1Click(Sender: TObject);
begin
  caption:=GetCDList;
end;    end.