Pausable System.Timers.Timer

Question

I found myself in need to precisely pause timer for indefinite time but still keep it's state, not to restart it after pause, but literally pause it, like you can do on your watches or phone app. The problem is that Timers.Timer has only Stop()/Start() which will reset it and Enabled does just the same.

Answer 1

using System;
using System.Timers;

namespace zLib {
    /// <summary>
    /// System.Timers.Timer modified to allow pausing.
    /// It saves start and pause time to release for reminder and correct back to original time
    /// </summary>
    public class PausableTimer : Timer {
        public PausableTimer(double interval) : base(interval) {
            Interval = interval;
            base.Elapsed += PausableTimer_Elapsed;
        }

        public PausableTimer() : base() {
            base.Elapsed += PausableTimer_Elapsed;
        }

        private void PausableTimer_Elapsed(object sender, ElapsedEventArgs e) {
            ElapsedEventHandler temp = Elapsed;
            if (temp != null) {
                temp(sender, e);
            }
        }

        private double interval;
        public new double Interval {
            get { return interval; } 
            set { interval = value; if (!wasPaused) base.Interval = interval; }
        }

        public new event ElapsedEventHandler Elapsed;

        private bool wasPaused;
        private DateTime startedAt;
        private DateTime pausedAt;

        public new void Start() {
            startedAt = DateTime.Now;
            base.Start();
        }

        public void Pause() {
            wasPaused = true;
            pausedAt = DateTime.Now;
            base.Stop();
        }

        public void Release() {
            //Set temporal interval
            base.Interval = Interval - ((pausedAt - startedAt).TotalMilliseconds % Interval);
            base.Elapsed += PausableTimer_ElapsedAfterPause;
            base.Start();
        }

        private void PausableTimer_ElapsedAfterPause(object sender, ElapsedEventArgs e) {
            base.Interval = Interval;
            base.Elapsed -= PausableTimer_ElapsedAfterPause;
            wasPaused = false;
        }
    }
}