Fix DateTime values in Unity on Android when building with .NET 4.6 support

DateTimeExt.cs

    public static class DateTimeExt
    {
#if UNITY_ANDROID && NET_4_6 && !UNITY_EDITOR
        static int cachedOffset = 0;
#endif
        static int MillisecondsOffset
        {
            get
            {
#if !UNITY_ANDROID || !NET_4_6 || UNITY_EDITOR
                return 0;
#else
                if(cachedOffset == 0)
                {
                    var calendar = new AndroidJavaObject("java.util.GregorianCalendar");
                    var timeZone = calendar.Call<AndroidJavaObject>("getTimeZone");
                    cachedOffset = timeZone.Call<int>("getRawOffset");
                }
                return cachedOffset;
#endif
            }
        }

        /// <summary>
        /// The latest versions of Unity running .NET rutime 4.6 on Android have a defect that
        /// local times get reported as UTC and no timezone information is available.
        /// 
        /// WARNING: do not call this function during app startup, such as initializing fields
        /// in classes.
        /// </summary>
        /// <param name="utcTime"></param>
        /// <returns></returns>
        public static DateTime FixTime(this DateTime time)
        {
            if(time.Kind == DateTimeKind.Local)
            {
                return time.AddMilliseconds(MillisecondsOffset);
            }
            else if(time.Kind == DateTimeKind.Utc)
            {
                return time.AddMilliseconds(-MillisecondsOffset);
            }
            else
            {
                return time;
            }
        }

        public static DateTime? FixTime(this DateTime? time)
        {
            return time?.FixTime();
        }
    }

Hi! I need to get a specific time hour in Unity for Android, this script is interesting but there are no documentation about how to use.

This is a workaround for a bug in a very old version of Unity. You include the file in your project somewhere and then call FixTime() once on whatever DateTime objects you need to use.

Thanks, do you can help me with a way to geet the hour in Android?

I am developing a Oculus app and I need get a specific time zone, I created a way inscript but only run well in editor, in oculus don't run well. Thanks for attention.

I cannot use your method because I don't know hot to instance or use methods from static classes.

I'm not your C# instructor.

Nice, this was just a request if you don't want to answer is ok, thanks for your script.

I found the solution, thanks for your script, variable to be used have to be static.