GetFileSize provides no way to turn a filesize into a descriptive string, this algorithm does
function GetAFileSize(SizeInBytes: Integer): String;
const
Preffixes: array[0..3] of String = //Common file sizes preffixes
(' Bytes', ' KB', 'MB', ' GB'); //Change if you want to anything that suits
FormatSpecifier: array[Boolean] of String =
('%n', '%.2n'); //the way we format the string;
var
i: integer; //A counter
TmpSize: Real; //A temporary variable
begin
i := -1; //Avoid compiler complain
tmpSize := SizeInBytes; //Avoid compiler complain
while (i <= 3) do //Main cycle it is done while i < High(Preffixes) but since
// a file will rarely pass a GB up to 3
begin
TmpSize := TmpSize / 1024; //1 MB = 1024 KB, 1 KB = 1024 Bytes, 1 Byte = 8 Bits, 1 bit = nothing
inc( i ); //increment counter and select preffix string
if Trunc( TmpSize )= 0 then //we reached a maximum nuber of divisions so
begin
TmpSize := TmpSize * 1024; //Tmpsize was divided 1 time more than necessary
Break; //Exit of loop;
end;
end;
//Actual formatting routine
Result := Format(FormatSpecifier[((Frac(TmpSize)*10) >1)], [TmpSize]) + Preffixes[i];
end;
Notes of interest:
* These algorithm relies on delphi native format function, wich kind of limits it
* It isnot part of windows api, you have to copy and paste it whenever you use it
* Unlike windows api it has correct rounding and can be extended