Конвертируем байты (Convert byte into MB, GB etc.)

private static string ConvertByte(long lbyte, int type)
{
 long lSize = 0;
 string unit = "";

 long lnBYTE = 1;
        long lnKILO = 1024; //    ' 2^10
 long lnMEGA = 1048576; //   ' 2^20
        long lnGIGA = 1073741824; //   ' 2^30
 long lnTERA = 1099511627776; //   ' 2^40     

 if (lbyte > 0)
 {
  switch (type)
  {
   case 0: //kb
                lSize = lbyte / lnKILO;
    unit = "KB";
    break;
   case 1: //mb
    lSize = lbyte / lnMEGA;
    unit = "MB";
    break;
   case 3: //gb
    lSize = lbyte / lnGIGA;
    unit = "GB";
    break;
            case 4: //gb
                lSize = lbyte / lnTERA;
                unit = "Tera";
                break;
  }
 }

 return lSize.ToString() + " " + unit;
}