How can I parse "1:15 P.M." into a NodaTime LocalTime?

Question

Parsing "1:15 pm" is easy:

var pattern = LocalTimePattern.CreateWithInvariantCulture("h:mm tt");
var time = pattern.Parse("1:15 pm").Value;

However, this doesn't work with the similar forms "1:15 P.M.", "1:15 PM", or "1:15 p.m."

Is there any built in support for those other forms of am/pm specifier, or does it need to be handled with string pre-processing?

Answer 1

Firstly, the "1:15 PM" version should work already - it does for me.

If you want to allow "P.M" or "p.m". you'll need to create a culture with appropriate AM/PM signifiers. That's easy enough to do:

using System;
using System.Globalization;
using NodaTime.Text;
using NodaTime;

class Program
{
    static void Main()
    {
        var culture = (CultureInfo) CultureInfo.InvariantCulture.Clone();
        culture.DateTimeFormat.AMDesignator = "a.m.";
        culture.DateTimeFormat.PMDesignator = "p.m.";
        string text = "1:15 P.M.";
        var pattern = LocalTimePattern.Create("h:mm tt", culture);
        var value = pattern.Parse(text).Value;
        Console.WriteLine(value);
    }   
}

However, note that at this point, pm and am won't work - if you need to handle both formats, you'll need to create multiple patterns and see which one (if any) parses the text successfully.