delphi得到目录大小

function GetDirectorySize(const ADirectory:string):Integer;
var
    sr:TSearchRec;
begin
    Result:=0;
    if not DirectoryExists(ADirectory) then  exit;
    if FindFirst(ADirectory+'/*.*', faAnyFile, sr) = 0 then
    begin
        repeat
          if ((sr.Attr and faDirectory)=faDirectory) and(sr.Name<>'.') and (sr.Name<>'..') then  begin
             Result:=Result+GetDirectorySize(ADirectory+'/'+sr.Name) ;
          end else if (sr.Name <>'.') and (sr.Name<>'..') then  begin
             Result:=Result+sr.Size;
          end;
        until FindNext(sr) <> 0;
    FindClose(sr);
    end;
end;