/// <summary>
/// Builds a numeric regular expression pattern.
/// </summary>
/// <param name="digitCount">Number of digits to the left of the decimal point to accept. A value of zero accepts any number of digits.</param>
/// <param name="mathematicalSignOption">Determines how mathematical signs are handled.</param>
/// <param name="numberGroupSeparatorOption">Determines how number group separators are handled.</param>
/// <param name="decimalDigits">Number of digits to the right of the decimal point to accept.</param>
/// <param name="decimalDigitRequired">Determines if the <see cref="decimalDigits"/> is required or optional.</param>
/// <param name="whiteSpaceOption">Determines how white space is handled.</param>
/// <param name="culture">The culture for which the regular expression is intended to be used. Defaults to the current culture.</param>
public static string BuildPattern(
int digitCount = 0,
MathematicalSignOption mathematicalSignOption = MathematicalSignOption.None,
NumberGroupSeparatorOption numberGroupSeparatorOption = NumberGroupSeparatorOption.None,
int decimalDigits = 0,
bool decimalDigitRequired = false,
WhiteSpaceOption whiteSpaceOption = WhiteSpaceOption.None,
CultureInfo culture = null)
{
culture = culture ?? CultureInfo.CurrentCulture;
return(Pattern
.AddDigitCount(digitCount)
.AddMathematicalSignOption(mathematicalSignOption, culture.NumberFormat)
.AddNumberGroupSeparatorOption(numberGroupSeparatorOption, culture.NumberFormat)
.AddDecimalDigits(decimalDigits, decimalDigitRequired, culture.NumberFormat)
.AddWhiteSpaceOption(whiteSpaceOption));
}
/// <summary>
/// Builds a <see cref="System.Text.RegularExpressions.Regex"/> object with a numeric pattern.
/// </summary>
/// <param name="digitCount">Number of digits to the left of the decimal point to accept. A value of zero accepts any number of digits.</param>
/// <param name="mathematicalSignOption">Determines how mathematical signs are handled.</param>
/// <param name="numberGroupSeparatorOption">Determines how number group separators are handled.</param>
/// <param name="decimalDigits">Number of digits to the right of the decimal point to accept.</param>
/// <param name="decimalDigitRequired">Determines if the <see cref="decimalDigits"/> is required or optional.</param>
/// <param name="whiteSpaceOption">Determines how white space is handled.</param>
/// <param name="culture">The culture for which the regular expression is intended to be used. Defaults to the current culture.</param>
public static Regex BuildRegex(
int digitCount = 0,
MathematicalSignOption mathematicalSignOption = MathematicalSignOption.None,
NumberGroupSeparatorOption numberGroupSeparatorOption = NumberGroupSeparatorOption.None,
int decimalDigits = 0,
bool decimalDigitRequired = false,
WhiteSpaceOption whiteSpaceOption = WhiteSpaceOption.None,
CultureInfo culture = null)
{
return(new Regex(BuildPattern(
digitCount,
mathematicalSignOption,
numberGroupSeparatorOption,
decimalDigits,
decimalDigitRequired,
whiteSpaceOption,
culture ?? CultureInfo.CurrentCulture)));
}
private static string AddNumberGroupSeparatorOption(this string numericPattern, NumberGroupSeparatorOption numberGroupSeparatorOption, NumberFormatInfo numberFormat)
{
if (numberFormat.NumberGroupSizes.Length > 1)
{
throw new NotImplementedException("Support for multiple number group sizes has not yet been implemented.");
}
string numberGroupSize = numberFormat.NumberGroupSizes[0].ToString();
string numberGroupSeparator = Regex.Escape(numberFormat.NumberGroupSeparator);
switch (numberGroupSeparatorOption)
{
case NumberGroupSeparatorOption.None:
return(numericPattern);
case NumberGroupSeparatorOption.Required:
return(Regex.Replace(numericPattern.Replace(@"\d", $@"[\d]{{1,{numberGroupSize}}}(?:{numberGroupSeparator}[\d]{{{numberGroupSize}}})"), @"(?<!\[)\+(?!\])", "*"));
case NumberGroupSeparatorOption.Optional:
return(Regex.Replace(numericPattern.Replace(@"\d", $@"[\d]{{1,{numberGroupSize}}}(?:{numberGroupSeparator}?[\d]{{{numberGroupSize}}})"), @"(?<!\[)\+(?!\])", "*"));
default:
throw new ArgumentOutOfRangeException(nameof(numberGroupSeparatorOption), numberGroupSeparatorOption, null);
}
}
