public static bool CanParse(string s)
{
bool returnValue = false;
NthParser parsedValue = null;
returnValue = NthParser.TryParse(s, out parsedValue);
return(returnValue);
}
public static NthParser Parse(string s)
{
NthParser returnValue = NthParser.Default;
if (!NthParser.TryParse(s, out returnValue))
{
throw new FormatException();
}
return(returnValue);
}
private DateTime _GetDate(int year, int month, Division division, int n)
{
DateTime returnValue = DateTime.MinValue;
//
// Get the first day of the month and then adjust the date
//
DateTime firstDayOfMonth = new DateTime(year, month, 1);
int dayOfWeek = (int)division;
int dayDifference = 0;
if ((int)firstDayOfMonth.DayOfWeek > dayOfWeek)
{
dayDifference = 7 - ((int)firstDayOfMonth.DayOfWeek - dayOfWeek);
returnValue = firstDayOfMonth.Add(TimeSpan.FromDays(dayDifference));
}
else
{
dayDifference = dayOfWeek - (int)firstDayOfMonth.DayOfWeek;
returnValue = firstDayOfMonth.Add(TimeSpan.FromDays(dayDifference));
}
//
// Get the maximum number of DayOfWeek's in the month
//
int maxDayOfWeek = NthParser.DayOfWeekCount((DayOfWeek)dayOfWeek, month, year);
int daysToAdd = 0;
if (n > maxDayOfWeek)
{
daysToAdd = (maxDayOfWeek - 1) * 7;
}
else
{
daysToAdd = (n - 1) * 7;
}
//
// Add the days to get the Nth occurrence
//
returnValue = returnValue.AddDays(daysToAdd);
return(returnValue);
}
public static bool TryParse(string s, out NthParser result)
{
bool returnValue = false;
result = NthParser.Default;
//
// Join the Ordinal enumerator names with the | character into a string
// and build the Ordinal pattern
//
string ordinalSection = String.Join("|", Enum.GetNames(typeof(Ordinal))).Replace("_", " ");
string ordinalPattern = string.Format(@"(?<Ordinal>({0})|([0-9]{{1,3}})(st|nd|rd|th))", ordinalSection);
//
// Join the Division enumerator names with the | character into a string
// and build the Division pattern
//
string section2 = String.Join("|", Enum.GetNames(typeof(Division))).Replace("_", " ");
string divisionPattern = string.Format("(?<Division>({0}))", section2);
//
// Join the Period enumerator names with the | character into a string
// and build the Period pattern
//
string section3 = String.Join("|", Enum.GetNames(typeof(Period))).Replace("_", " ");
string periodPattern = string.Format("(?<Period>({0}))", section3);
string pattern = string.Format(@"({0}\s{1}\s(of|in)\s{2})", ordinalPattern, divisionPattern, periodPattern);
Regex regex = new Regex(pattern, RegexOptions.IgnoreCase);
MatchCollection matches = regex.Matches(s);
if (matches.Count > 0)
{
GroupCollection groups = matches[0].Groups;
if (groups.Count >= 3)
{
//
// Used to convert strings to title case
//
CultureInfo cultureInfo = System.Threading.Thread.CurrentThread.CurrentCulture;
TextInfo textInfo = cultureInfo.TextInfo;
//
// Get the Ordinal
//
string interval = textInfo.ToTitleCase(groups["Ordinal"].Value).Replace(" ", "_");
Ordinal parsedValue = Ordinal.Other;
if (Enum.TryParse <Ordinal>(interval, out parsedValue))
{
result.Ordinal = parsedValue;
}
else
{
//
// Need to parse the integer. The right two characters will
// always be st, nd, rd or th
//
string intText = interval.Substring(0, interval.Length - 2);
result.N = int.Parse(intText);
}
//
// Get the Division
//
string division = textInfo.ToTitleCase(groups["Division"].Value).Replace(" ", "_");
result.Division = (Division)Enum.Parse(typeof(Division), division, true);
//
// Get the Period
//
string period = textInfo.ToTitleCase(groups["Period"].Value).Replace(" ", "_");
result.Period = (Period)Enum.Parse(typeof(Period), period, true);
returnValue = true;
}
}
return(returnValue);
}
