How to check if a drive is ready

Problem/Question/Abstract:

How to check whether there is a floppy or CD inside the drives?

Answer:

function DiskInDrive(const Drive: char): Boolean;
var
  DrvNum: byte;
  EMode: Word;
begin
  result := false;
  DrvNum := ord(Drive);
  if DrvNum >= ord('a') then
    dec(DrvNum, $20);
  EMode := SetErrorMode(SEM_FAILCRITICALERRORS);
  try
    if DiskSize(DrvNum - $40) <> -1 then
      result := true
    else
      messagebeep(0);
  finally
    SetErrorMode(EMode);
  end;
end;