Finding if a string contains a date and time

Question

I am working on a project where I am reading in a file which could come in two different formats, one includes a date and time and the other doesn't.

When I read in the first line I need to check whether the string contains the date and time or not and read the file and based on the check read the file in a certain way.

I'm guessing this would be some kind of regular expression but have no idea where to start and can't find anything relevant.

Thanks for any help you can provide.

UPDATE I don't think I've been very clear as to what I am asking. When I read the log file line by line the line may come in as:

Col1   Col2  Col3  Col4  Col5 

Sometimes the line may come in as

Col1  17-02-2013 02:05:00 Col2  Col3  Col4  Col5

When I read the line I need to do a check whether there is a date and time string contained within the string.

Answer 1

If the format of the date has been defined, you can use Regex to solve it.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;

namespace RegTest
{
    class Program
    {
        static void Main(string[] args)
        {
            string testDate = "3214312402-17-2013143214214";
            Regex rgx = new Regex(@"\d{2}-\d{2}-\d{4}");
            Match mat = rgx.Match(testDate);
            Console.WriteLine(mat.ToString());
            Console.ReadLine();
        }
    }
}

Answer 2

   string s = " Subject: Current account balances for 21st December 2017 and 2nd January 2019 mnmnm ";//here is u r sample string

   s = s.ToLower();
   string newStrstr = Regex.Replace(s, " {2,}", " ");//remove more than whitespace
   string newst = Regex.Replace(newStrstr, @"([\s+][-/./_///://|/$/\s+]|[-/./_///://|/$/\s+][\s+])", "/");// remove unwanted whitespace eg 21 -dec- 2017 to 21-07-2017
   newStrstr = newst.Trim();
   Regex rx = new Regex(@"(st|nd|th|rd)");//21st-01-2017 to 21-01-2017
   string sp = rx.Replace(newStrstr, "");
   rx = new Regex(@"(([0-2][0-9]|[3][0-1]|[0-9])[-/./_///://|/$/\s+]([0][0-9]|[0-9]|[1][0-2]|jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec|january|february|march|april|may|june|july|augu|september|october|november|december)[-/./_///:/|/$/\s+][0-9]{2,4})");//a pattern for regex to check date format. For August we check Augu since we replaced the st earlier
   MatchCollection mc = rx.Matches(sp);//look for strings that satisfy the above pattern regex

   List<DateTime> dates=new List<DateTime>(); //Create a list to store the detected dates

   foreach(Match m in mc)
   {
        string s2=Regex.Replace(m.ToString(), "augu", "august");
        dates.Add(DateTime.Parse(s2);
   }