//nyorganci@hotmail.com
var
iFileHandle: Integer;
begin
if OpenDialog1.Execute then begin
iFileHandle := FileOpen(OpenDialog1.FileName, fmOpenRead);
label1.caption:=inttostr(getfilesize(iFileHandle,nil))+' Bayt.';//getfilesize delphinin degil,Windows Api fonksiyonu.
FileClose(iFileHandle);
end;