private bool ValidateNumber()
{
const int modValue = 97;
const int modResult = 1;
var wholeString = string.Concat(Bban, CountryCode, Checksum.ToString(CultureInfo.InvariantCulture).PadLeft(ChecksumLength, '0'));
var sb = new StringBuilder();
for (var i = 0; i < wholeString.Length; ++i)
#if NET20
{ sb.Append(CharExtensions.GetNumericValue(wholeString[i])); }
#else
{ sb.Append(wholeString[i].GetNumericValue()); }
#endif
var valuedString = sb.ToString();
#if !NET40
// Little workaround for not having a BigInteger class.
const int maxLength = 9;
long currentSum = 0;
while (valuedString.Length > 0)
{
string nextString;
int subStrLength;
if (currentSum > 0)
{
var sumStr = currentSum.ToString(CultureInfo.InvariantCulture);
subStrLength = maxLength - sumStr.Length;
subStrLength = Math.Min(subStrLength, valuedString.Length);
nextString = sumStr + valuedString.Substring(0, subStrLength);
}
else
{
subStrLength = Math.Min(maxLength, valuedString.Length);
nextString = valuedString.Substring(0, subStrLength);
}
valuedString = valuedString.Remove(0, subStrLength);
currentSum = long.Parse(nextString) % modValue;
}
return(currentSum % modValue == modResult);
#else
// Since .NET 4.0 and above have a BigInteger class, we use that.
var ibanValue = BigInteger.Parse(valuedString);
return(ibanValue % modValue == modResult);
#endif
}
private static bool ValidateBban(string bban)
{
bban = bban.Trim();
if (bban.Length > MaxBbanLength)
{
return(false);
}
for (var i = 0; i < bban.Length; ++i)
{
#if NET20
if (!char.IsDigit(bban[i]) && !CharExtensions.IsValidChar(bban[i]))
#else
if (!char.IsDigit(bban[i]) && !bban[i].IsValidChar())
#endif
{ return(false); }
}
return(true);
}