protected override VatValidationResult OnValidate(string vat)
{
if (vat.Length == 9)
{
if (vat[7] != '1')
{
return(VatValidationResult.Failed("9 character VAT numbers should have 1 in 8th position."));
}
var sum = 0;
for (var index = 0; index < 8; index++)
{
sum += vat[index].ToInt() * (index + 1);
}
var checkDigit = sum % 11;
if (checkDigit == 10)
{
checkDigit = vat.Sum(Multipliers);
}
if (checkDigit == 10)
{
checkDigit = 0;
}
var isValid = checkDigit == vat[8].ToInt();
return(!isValid
? VatValidationResult.Failed("Invalid LT vat: checkValue")
: VatValidationResult.Success());
}
return(TemporarilyRegisteredTaxPayers(vat));
}
protected override VatValidationResult OnValidate(string vat)
{
var sum = vat.Sum(Multipliers);
// Old VAT numbers (pre 2020) - Modulus 11 test
var checkMod11 = sum % 11;
if (checkMod11 > 9)
{
checkMod11 = 0;
}
var isValidMod11 = checkMod11 == vat[8].ToInt();
if (isValidMod11)
{
return(VatValidationResult.Success());
}
// New VAT numbers (post 2020) - Modulus 97 test
const string stringValueNl = "2321";
const string stringValueB = "11";
vat = vat.Replace("B", stringValueB);
var isValidMod97 = long.Parse(stringValueNl + vat) % 97 == 1;
return(!isValidMod97
? VatValidationResult.Failed("Invalid NL vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
if (RegexType2.IsMatch(vat))
{
vat = "0" + vat.Substring(2, 7)
+ vat.Substring(0, 1)
+ vat.Substring(7, 8);
}
var sum = vat.Sum(Multipliers);
// If the number is type 3 then we need to include the trailing A or H in the calculation
if (RegexType3.IsMatch(vat))
{
// Add in a multiplier for the character A (1*9=9) or H (8*9=72)
if (vat[8] == 'H')
{
sum += 72;
}
else
{
sum += 9;
}
}
var checkDigit = sum % 23;
var isValid = vat[7] == (checkDigit == 0 ? 'W' : (char)(checkDigit + 64));
return(!isValid
? VatValidationResult.Failed("Invalid IE vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
// Only do check digit validation for standard VAT numbers
if (vat.Length != 8)
{
return(VatValidationResult.Success());
}
var sum = vat.Sum(Multipliers);
var checkDigit = 11 - sum % 11;
if (checkDigit == 10)
{
checkDigit = 0;
}
if (checkDigit == 11)
{
checkDigit = 1;
}
var isValid = checkDigit == vat[7].ToInt();
return(!isValid
? VatValidationResult.Failed("Invalid CZ vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var product = 10;
for (var index = 0; index < 8; index++)
{
var sum = (vat[index].ToInt() + product) % 10;
if (sum == 0)
{
sum = 10;
}
product = 2 * sum % 11;
}
var val = 11 - product;
var checkDigit = val == 10
? 0
: val;
var isValid = checkDigit == vat[8].ToInt();
return(!isValid
? VatValidationResult.Failed("Invalid DE vat: checkValue")
: VatValidationResult.Success());
}
private static VatValidationResult TemporarilyRegisteredTaxPayers(string vat)
{
if (vat[10] != '1')
{
return(VatValidationResult.Failed("Temporarily Registered Tax Payers should have 11th character one"));
}
var total = vat.Sum(MultipliersTemporarily);
// double check digit calculation
if (total % 11 == 10)
{
total = vat.Sum(MultipliersDoubleCheck);
}
// Establish check digit.
total %= 11;
if (total == 10)
{
total = 0;
}
var isValid = total == vat[11].ToInt();
return(!isValid
? VatValidationResult.Failed("Invalid LT vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var end = vat.Length - 1;
var controlDigit = vat[end].ToInt();
var slice = vat.Slice(0, end);
vat = slice.PadLeft(9, '0');
var sum = vat.Sum(Multipliers);
var checkDigit = sum * 10 % 11;
if (checkDigit == 10)
{
checkDigit = 0;
}
var isValid = checkDigit == controlDigit;
return(!isValid
? VatValidationResult.Failed("Invalid RO vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var isValid = int.Parse(vat.Substring(0, 6)) % 89 == int.Parse(vat.Substring(6, 2));
return(!isValid
? VatValidationResult.Failed("Invalid LU vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var nr = ulong.Parse(vat);
var isValid = nr % 11 == 0;
return(!isValid
? VatValidationResult.Failed("Invalid SK vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var sum = vat.Sum(Multipliers);
var isValid = sum % 11 == 0;
return(!isValid
? VatValidationResult.Failed("Invalid DK vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var sum = vat.Sum(Multipliers);
var checkDigit = 37 - sum % 37;
var isValid = checkDigit == int.Parse(vat.Substring(6, 2));
return(!isValid
? VatValidationResult.Failed("Invalid MT vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
if (int.Parse(vat.Substring(0, 2)) == 12)
{
return(VatValidationResult.Failed("CY vat first 2 characters cannot be 12"));
}
var result = 0;
for (var index = 0; index < 8; index++)
{
var temp = vat[index].ToInt();
if (index % 2 == 0)
{
switch (temp)
{
case 0:
temp = 1;
break;
case 1:
temp = 0;
break;
case 2:
temp = 5;
break;
case 3:
temp = 7;
break;
case 4:
temp = 9;
break;
default:
temp = temp * 2 + 3;
break;
}
}
result += temp;
}
var checkDigit = result % 26;
var isValid = vat[8].ToInt() == checkDigit + 65;
return(!isValid
? VatValidationResult.Failed("Invalid CY vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var sum = vat.Sum(Multipliers);
var checkDigit = 11 - sum % 11;
if (checkDigit > 9)
{
checkDigit = 0;
}
var isValid = checkDigit == vat[8].ToInt();
return(!isValid
? VatValidationResult.Failed("Invalid PT vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var validationKey = vat.Substring(0, 2);
var val = int.Parse(vat.Substring(2));
if (!int.TryParse(validationKey, out var temp))
{
return(VatValidationResult.Success());
}
var checkDigit = (12 + 3 * (val % 97)) % 97;
var isValid = checkDigit == temp;
return(!isValid
? VatValidationResult.Failed("Invalid FR vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
// Only check the legal bodies
if (Regex.IsMatch(vat, "/^[0-3]/"))
{
var result = Regex.IsMatch(vat, "^[0-3][0-9][0-1][0-9]");
return(!result
? VatValidationResult.Failed("Invalid LV vat: checkValue")
: VatValidationResult.Success());
}
var sum = vat.Sum(Multipliers);
var checkDigit = sum % 11;
if (checkDigit == 4 && vat[0] == '9')
{
checkDigit -= 45;
}
if (checkDigit == 4)
{
checkDigit = 4 - checkDigit;
}
else
{
if (checkDigit > 4)
{
checkDigit = 14 - checkDigit;
}
else
{
if (checkDigit < 4)
{
checkDigit = 3 - checkDigit;
}
}
}
var isValid = checkDigit == vat[10].ToInt();
return(!isValid
? VatValidationResult.Failed("Invalid LV vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
if (vat.Length == 10 && vat[0] != '0')
{
return(VatValidationResult.Failed("First character of 10 digit numbers should be 0."));
}
if (vat.Length == 9)
{
vat = vat.PadLeft(10, '0');
}
// Modulus 97 check on last nine digits
var isValid = 97 - int.Parse(vat.Substring(0, 8)) % 97 == int.Parse(vat.Substring(8, 2));
return(!isValid
? VatValidationResult.Failed("Invalid BE vat: checkValue.")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
bool isValid;
if (vat.Length == 9)
{
isValid = Bg9DigitsVat(vat);
return isValid ? VatValidationResult.Success() : VatValidationResult.Failed("Invalid 9 digits vat.");
}
if (BgPhysicalPerson(vat))
{
return VatValidationResult.Success();
}
isValid = BgForeignerPhysicalPerson(vat) || BgMiscellaneousVatNumber(vat);
return !isValid
? VatValidationResult.Failed("")
: VatValidationResult.Success();
}
protected override VatValidationResult OnValidate(string vat)
{
// The last three digits are the issuing office, and cannot exceed more 201
if (int.Parse(vat.Substring(0, 7)) == 0)
{
return(VatValidationResult.Failed(""));
}
var temp = int.Parse(vat.Substring(7, 3));
if ((temp < 1 || temp > 201) && temp != 999 && temp != 888)
{
return(VatValidationResult.Failed(""));
}
var index = 0;
var sum = 0;
foreach (var m in Multipliers)
{
temp = vat[index++].ToInt() * m;
sum += temp > 9
? (int)Math.Floor(temp / 10D) + temp % 10
: temp;
}
var checkDigit = 10 - sum % 10;
if (checkDigit > 9)
{
checkDigit = 0;
}
var isValid = checkDigit == vat[10].ToInt();
return(!isValid
? VatValidationResult.Failed("Invalid IT vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var index = 0;
var sum = 0;
foreach (var m in Multipliers)
{
var temp = vat[index++].ToInt() * m;
sum += temp > 9 ? (int)Math.Floor(temp / 10D) + temp % 10 : temp;
}
var checkDigit = 10 - sum % 10;
if (checkDigit == 10)
{
checkDigit = 0;
}
var isValid = checkDigit == vat[9].ToInt();
return(!isValid
? VatValidationResult.Failed("Invalid SE vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var index = 1;
var sum = 0;
foreach (var digit in Multipliers)
{
var temp = vat[index++].ToInt() * digit;
sum += temp > 9 ? (int)Math.Floor(temp / 10D) + temp % 10 : temp;
}
var checkDigit = 10 - (sum + 4) % 10;
if (checkDigit == 10)
{
checkDigit = 0;
}
var isValid = checkDigit == vat[8].ToInt();
return(!isValid
? VatValidationResult.Failed($"Invalid {CountryCode} vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var product = 10;
for (var index = 0; index < 10; index++)
{
int sum = (vat[index].ToInt() + product) % 10;
if (sum == 0)
{
sum = 10;
}
product = 2 * sum % 11;
}
var checkDigit = (product + vat[10].ToInt()) % 10;
var isValid = checkDigit == 1;
return(!isValid
? VatValidationResult.Failed("Invalid HR vat: checkValue")
: VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
return(VatValidationResult.Success());
}
protected override VatValidationResult OnValidate(string vat)
{
var prefix = vat.Substring(0, 2);
int no;
if (prefix == "GD" && int.TryParse(vat.Substring(2, 3), out no))
{
// return no < 500;
}
if (prefix == "HA" && int.TryParse(vat.Substring(2, 3), out no))
{
// return no > 499;
}
if (prefix == "HA")
{
return(VatValidationResult.Failed(""));
}
if (vat[0].ToInt() == 0)
{
return(VatValidationResult.Failed("0 VAT numbers disallowed"));
}
// Check range is OK for modulus 97 calculation
no = int.Parse(vat.Substring(0, 7));
var total = vat.Sum(Multipliers);
// Old numbers use a simple 97 modulus, but new numbers use an adaptation of that (less 55). Our
// Establish check digits by subtracting 97 from total until negative.
var cd = total;
while (cd > 0)
{
cd -= 97;
}
// Get the absolute value and compare it with the last two characters of the VAT number. If the
// same, then it is a valid traditional check digit. However, even then the number must fit within
// certain specified ranges.
cd = Math.Abs(cd);
if (cd == int.Parse(vat.Substring(7, 2)) && no < 9990001 && (no < 100000 || no > 999999) &&
(no < 9490001 || no > 9700000))
{
return(VatValidationResult.Success());
}
// Now try the new method by subtracting 55 from the check digit if we can - else add 42
if (cd >= 55)
{
cd -= 55;
}
else
{
cd += 42;
}
var isValid = cd == int.Parse(vat.Substring(7, 2)) && no > 1000000;
return(!isValid
? VatValidationResult.Failed("Invalid GB vat: checkValue")
: VatValidationResult.Success());
}