How to check to see if a drive is ready

Gustav Evertsson
Ratings: 0, Votes: 0

The following function accepts a drive letter as a parameter, and it will return a boolean value that indicates whether or not there is a disk in the drive.

function DiskInDrive(Drive: Char): Boolean;
var
ErrorMode: word;
begin
{ make it upper case }

if Drive in ['a'..'z'] then Dec(Drive, $20);

{ make sure it's a letter }

if not (Drive in ['A'..'Z']) then
raise EConvertError.Create('Not a valid drive ID');

{ turn off critical errors }
ErrorMode := SetErrorMode(SEM_FailCriticalErrors);

try
{ drive 1 = a, 2 = b, 3 = c, etc. }
if DiskSize(Ord(Drive) - $40) = -1 then
Result := False
else
Result := True;
finally
{ restore old error mode }
SetErrorMode(ErrorMode);
end;
end;