how to extract string from regular expression and convert it to timespan?

Question

I'm trying to extract string from regular expression and convert it to string and converting it to Timespan again.

static Regex myTimePattern = new Regex(@"((\d+)+(\:\d+))$");

static TimeSpan DurationTimespan(string s)
{
    if (s == null) throw new ArgumentNullException("s");

    Match m = myTimePattern.Match(s);

    if (!m.Success) throw new ArgumentOutOfRangeException("s");

    string hh = m.Groups[0].Value.PadRight(2, '0');
    string mm = m.Groups[2].Value.PadRight(2, '0');

    int hours = int.Parse(hh);
    int minutes = int.Parse(mm);

    if (minutes < 0 || minutes > 59) throw new ArgumentOutOfRangeException("s");

    TimeSpan value = new TimeSpan(hours, minutes, 0);
    return value;
}

string hh shows = "30:00" and mm shows: "30". The time in my textbox from which data is collected is : "01:30:00". Please help me find a way.

please show the original text which contains the desired information — Lei Yang, Jul 11 '17 at 07:21
Using Regex here is not needed and way too complicated. Better use `var parts = s.Split(':')` which gives `["01", "30", "00"]` and then go from there. See fiddle: https://dotnetfiddle.net/zbBVMV — Peter B, Jul 11 '17 at 07:33
If your goal is to get a `TimeSpan` from a string formatted as `hh:mm:ss`, why not just directly parse it using `TimeSpan.Parse` method? — IronGeek, Jul 11 '17 at 07:33
Thanx IronGeek , your approach was much cleaner. It worked right away. — , Jul 11 '17 at 08:19

vasek · Answer 1 · 2017-07-11T07:28:40.817

1

If your regular expression would look like this:

   static Regex myTimePattern = new Regex(@"(\d+)+\:(\d+)\:\d+$");

Then you can easily retreive groups as follows:

   string hh = m.Groups[1].Value.PadRight(2, '0');
   string mm = m.Groups[2].Value.PadRight(2, '0');

Do you have a reason why not to use Parse string in HH.mm format to TimeSpan ?

edited Jul 11 '17 at 07:28

answered Jul 11 '17 at 07:27

vasek

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This regex only gets minutes and seconds – Romano Zumbé Jul 11 '17 at 07:28

score 0 · Accepted Answer · answered Jul 11 '17 at 07:27

Your regex covers only mm and ss. You could use this:

static Regex myTimePattern = new Regex(@"(\d{1,2}):(\d{1,2}):(\d{1,2})");
static TimeSpan DurationTimespan( string s )
{
        if ( s == null ) throw new ArgumentNullException("s");
        Match m = myTimePattern.Match(s);
        if ( ! m.Success ) throw new ArgumentOutOfRangeException("s");
        string hh = m.Groups[1].Value;
        string mm = m.Groups[2].Value;

        int hours   = int.Parse( hh );
        int minutes = int.Parse( mm );
        if ( minutes < 0 || minutes > 59 ) throw new ArgumentOutOfRangeException("s");
        TimeSpan value = new TimeSpan(hours , minutes , 0 );
        return value ;
    }

Von Abanes · Answer 3 · 2017-07-11T07:35:45.400

        static Regex myTimePattern = new Regex(@"^([0-9]|0[0-9]|1[0-9]|2[0-3]):[0-5][0-9]$");
            static TimeSpan DurationTimespan(string s)
            {
                if (s == null) throw new ArgumentNullException("s");
                Match m = myTimePattern.Match(s);
                if (!m.Success)
                    throw new ArgumentOutOfRangeException("s");

                DateTime DT = DateTime.Parse(s);
                TimeSpan value = new TimeSpan(DT.Hour, DT.Minute, 0);

                if (DT.Minute < 0 || DT.Minute > 59)
                    throw new ArgumentOutOfRangeException("s");

                return value;
            }

how to extract string from regular expression and convert it to timespan?

3 Answers3