Unity C#, How to addition X days to a date?

Question

In this part of code sDate show current date 2016/11/16, Now what is best way to add 7 days to current date? for example if current date is 2016/11/29 + 7 change to 2016/12/06. I'm looking for a way to addition an int value to a date.

string Year;
string Month;
string Day;
float time;
string sDate;

void Start () 
{

        Year = System.DateTime.Now.Year.ToString();
        Month = System.DateTime.Now.Month.ToString();
        Day = System.DateTime.Now.Day.ToString();

        int Y = int.Parse (Year);
        int M = int.Parse (Month);
        int D = int.Parse (Day);


        if (Y >= 2016 & M >= 11 & D >= 21) 
        {
            sDate = Year + "/" + Month + "/" + Day + " | Expired";
            Debug.Log (sDate);

            Application.Quit ();
        } 
        else 
        {
            sDate = Year + "/" + Month + "/" + Day + " | Working";
            Debug.Log ("System date: " + sDate);
        }

}

Answer 1

All you need to do is use the standard DateTime function AddDays :

DateTime result = original.AddDays(n);

where original is the original date and n is the number of days you want to add.

I'd also check the rest of the documentation on the DateTime structure as there are a lot simpler ways of doing what you are trying here. As mentioned in the comments you can construct a DateTime object from it's components:

DateTime referenceDate = new DateTime(2016, 11, 15);

and then do comparisons on that:

if (testDate >= referenceDate)
{
    // Do something
}

etc.