Converting a 12 hour time string to a 24 hour time string

Input - Standard input - HH:MM:SS[AM|PM] format.

Examples:

• 12:00:00AM

• 12:00:00PM

• 01:00:10AM

• 01:00:10PM

The program reads one line per instance.

Output - military format (24 hour format):

• 00:00:00

• 12:00:00

• 01:00:10

• 13:00:10

using System;

class Solution {
    static void Main(String[] args) {
        var time = Console.ReadLine().Trim();
        MilitaryTime mt = new MilitaryTime(time);
        Console.WriteLine(mt);
    }

    class MilitaryTime{
        string newTime = null;
        string originalTime = null;

        string correctHour(string time){
            var ampmLen = 2;
            var ampm = time.Substring(time.Length-ampmLen, ampmLen);
            var hourIndex = 0;
            var hour = time.Split(':')[hourIndex];
            var h = hour;
            if(ampm.Equals("PM")){
                h = (int.Parse(hour) + 12).ToString();
            }
            if(hour.Equals("12") || hour.Equals("24")){
                if(ampm.Equals("AM")){
                    h = "00";
                } else if(ampm.Equals("PM")){
                    h = "12";
                }
            }
            return h;
        }
        string minutesAndSeconds(string time){
            var ampmLen = 2;
            var hourLen = 2;
            var startIndex = hourLen; // since we are taking after hour HH:MM:SS 
            return time.Substring(startIndex, time.Length - ampmLen - hourLen);
        }
        public MilitaryTime(string time){
            originalTime = time;
        }
        public override string ToString(){
            if(string.IsNullOrEmpty(newTime)){
                newTime = correctHour(originalTime) + minutesAndSeconds(originalTime);
            }
            return newTime;
        }
    }
}

• Is this code smelly?

• I re-factored code to this state, but did I miss anything?

• Is there a better way to solve this problem, using .net classes and features I might have missed?

• Does it look like that it's writt

Here's how to parse dates and times using built-in .Net libraries:

static void Main()
{
    string strTime = "01:00:10AM";
    DateTime time;
    if (DateTime.TryParseExact(strTime, "hh:mm:sstt", null, 
        System.Globalization.DateTimeStyles.None, out time))
    {
        Console.WriteLine("Parsed \"{0}\" as {1:HH\\:mm\\:ss}", strTime, time);
    }
    else
    {
        Console.WriteLine("Could not parse \"{0}\" as a DateTime", strTime);
    }
    Console.ReadLine();
}

Some points to note:

• I'm not reinventing the wheel. The .Net DateTime library is the best way to handle points in time. (Use TimeSpan for duration)

• I'm using custom DateTime format strings for both parsing the string and displaying the parsed DateTime result.

• I'm using the TryParse pattern the .Net supplies for converting strings to various built-in types: e.g., int.TryParse, double.TryParse, etc.

• In the output, I want to display the parsed time as HH:mm:ss (note that capital H is 24 hour time and lowercase h is 12 hour time). I have to escape the colons in there because of how string.Format works. You escape colons using backslashes like this HH\:mm\:ss. The problem is that you then have to escape the backslashes (or use verbatim strings). You do that with an extra backslash like this HH\\:mm\\:ss

StackExchange Code Review Q#110191, answer score: 5