public static ValidationTestValue CheckValidation(this Base32Encoding encoder, string encoded) { Exception toBytesError = null; try { encoder.ToBytes(encoded); } catch (Exception ex) { toBytesError = ex; } var validationResult = encoder.Validate(encoded); var vr2 = encoder.Validate(encoded, 0, encoded?.Length ?? 0); var vr3 = encoder.Validate(encoded != null ? "test" + encoded : null, 4, encoded?.Length ?? 0); if (validationResult != vr2 || validationResult != vr3) { throw new Exception("CheckValidation error"); } return(new ValidationTestValue(validationResult, toBytesError)); }