Delphi 两种获取文件大小的方法 (支持大文件)

function GetFileSize(const strFileName: string): Int64;
 var
   Handle: THandle;
   FindData: TWin32FindData;
   nFileSize: Int64;
 begin
   Result := -1;
   Handle := FindFirstFile(PChar(strFileName), FindData);
   if Handle <> INVALID_HANDLE_VALUE then
   begin
     Windows.FindClose(Handle);
     if (FindData.dwFileAttributes and FILE_ATTRIBUTE_DIRECTORY) = 0 then
     begin
       Int64Rec(nFileSize).Lo := FindData.nFileSizeLow;
       Int64Rec(nFileSize).Hi := FindData.nFileSizeHigh;
       Result := nFileSize;
     end;
   end;
 end;方法2:
 function GetFileSize(const strFileName: string): Int64;
 var
   sr: TSearchRec;
 begin
   if not FileExists(strFileName) then
   begin
     Result := -1;
     Exit;
   end;
   if FindFirst(strFileName, faAnyFile, sr) = 0 then
     Result := Int64(sr.FindData.nFileSizeHigh) shl 32 + Int64(sr.FindData.nFileSizeLow)
   else
     Result := -1;
   FindClose(sr);
 end;