ExtractDates

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace _19.EtractDates
{
    /*Write a program that extracts from a given text all dates that match the format DD.MM.YYYY.
     * Display them in the standard date format for Canada.*/
    class Program
    {
        static void Main(string[] args)
        {
            string text = "I was born at 14.06.1980. My sister was born at 3.7.1984. In 5/1999 I graduated my high school. The law says (see section 7.3.12) that we are allowed to do this (section 7.4.2.9).";

            foreach (var extracted in Regex.Matches(text, @"((((0?[1-9])|[12][0-9]|3[01])\.((0?[13578])|(1[02])))|(((0?[1-9])|[12][0-9]|30)\.((0?[469])|11))|(((0?[1-9])|[12][0-9])\.(0?2)))\.\d{4}"))
            {
                string extractedToString = Convert.ToString(extracted);
                DateTime date = DateTime.ParseExact(extractedToString, "dd.MM.yyyy", CultureInfo.InvariantCulture);
                Console.WriteLine(date.ToString(CultureInfo.GetCultureInfo("en-CA")));
            }
        }
    }
}