Regular expression to validate valid time

Question

Can someone help me build a regular expression to validate time?

Valid values would be from 0:00 to 23:59.

When the time is less than 10:00 it should also su

Answer 1

I don't want to steal anyone's hard work but this is exactly what you're looking for, apparently.

using System.Text.RegularExpressions;

public bool IsValidTime(string thetime)
{
    Regex checktime =
        new Regex(@"^(20|21|22|23|[01]d|d)(([:][0-5]d){1,2})$");

    return checktime.IsMatch(thetime);
}

Answer 2

If you want to allow military and standard with the use of AM and PM (optional and insensitive), then you may want to give this a try.

^(?:(?:0?[1-9]|1[0-2]):[0-5][0-9]\s?(?:[AP][Mm]?|[ap][m]?)?|(?:00?|1[3-9]|2[0-3]):[0-5][0-9])$ 

Answer 3

    public bool IsTimeString(string ts)
    {
        if (ts.Length == 5 && ts.Contains(':'))
        {
            int h;
            int m;

            return int.TryParse(ts.Substring(0, 2), out h) &&
                   int.TryParse(ts.Substring(3, 2), out m) &&
                   h >= 0 && h < 24 &&
                   m >= 0 && m < 60;
        }
        else
            return false;
    }

Answer 4

The regex ^(2[0-3]|[01]d)([:][0-5]d)$ should match 00:00 to 23:59. Don't know C# and hence can't give you the relevant code.

/RS

Answer 5

Better!!!

    public bool esvalida_la_hora(string thetime)
    {
        Regex checktime = new Regex("^(?:0?[0-9]|1[0-9]|2[0-3]):[0-5][0-9]$");
        if (!checktime.IsMatch(thetime))
            return false;

        if (thetime.Trim().Length < 5)
            thetime = thetime = "0" + thetime;

        string hh = thetime.Substring(0, 2);
        string mm = thetime.Substring(3, 2);

        int hh_i, mm_i;
        if ((int.TryParse(hh, out hh_i)) && (int.TryParse(mm, out mm_i)))
        {
            if ((hh_i >= 0 && hh_i <= 23) && (mm_i >= 0 && mm_i <= 59))
            {
                return true;
            }
        }
        return false;
    }

Answer 6

I'd just use DateTime.TryParse().

DateTime time;
string timeStr = "23:00"

if(DateTime.TryParse(timeStr, out time))
{
  /* use time or timeStr for your bidding */
}