How to calculate difference between two real world times

Questions & Answers
1

I am making a reward system for my mobile game and I was wondering how do you calculate the difference between two real world times and if the difference between times is over 6 hours, set a variable to true.

This is so that if the player returns to the game after 6 hours they can receive a reward for doing so.

2

Use System.DateTime.

System.DateTime datevalue1 = new System.DateTime(2015,1,1);
System.DateTime datevalue2 = System.DateTime.Now;
double hours = (datevalue2 - datevalue1).TotalHours;

Debug.Log ("It has been " + hours.ToString() + " hours since the beginning of the year");