using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"^((19\d{2})|(20\d{2}))-(((02)-(0[1-9]|[1-2][0-9]))|(((0(1|[3-9]))|(1[0-2]))-(0[1-9]|[1-2][0-9]|30))|((01|03|05|07|08|10|12)-(31)))$";
string input = @"2000-12-31";
Match m = Regex.Match(input, pattern);
Console.WriteLine("'{0}' found at index {1}", m.Value, m.Index);
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx