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            "Delphi X-Files" <www.DelphiXFiles.narod.ru>"
                       "Определение дисков"
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function DriveExists(Drive: Byte): Boolean;
begin
  Result := Boolean (GetLogicalDrives And (1 shl Drive));
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  D: Byte;
begin
  For D := 0 to 25 do
   If DriveExists(D) Then
    begin
     ListBox1.Items.Add(Chr(D+$41));
    end;
end; 
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