Hayden-R

Floppy in drive function

Here a little function that checks to see if a drive has some media in it, e.g. a floppy drive has a floppy disk in it, or a CD ROM drive has a disk in it. Thus before trying to save or load a file you can check the drive and present the user with a meaningful error message rather than just getting a IO error.

function MediaInDrive(const Drive: string): Boolean;
{works with WinNT and Win95}
{NOTE: Drive must in the from 'A:', this is so
 can use function ExtractFileDrive for a file name.}
var
  OldErrorMode: Cardinal;
  SearchRec: TSearchRec;
  RetVal: Integer;
begin
  {set OS error mode so system does not display the
   critical-error-handler message box when such an
   error occurs. Instead, the operating system sends
   the error to the calling process.}
  OldErrorMode := SetErrorMode( SEM_FAILCRITICALERRORS );
  try
    {swicth off IO checking}
    {$I-}
    RetVal := FindFirst( Drive + '\*.*', faAnyfile, SearchRec );
    FindClose( SearchRec );
    {switch on IO checking}
    {$I+}
    case Retval of
        0: Result := True; {disk with files}
      -18: Result := True; {disk with no files}
    else
      Result := False; {no disk}
    end;
  finally
    {Reset OS error mode}
    SetErrorMode( OldErrorMode );
  end;
end;