C# - Difference between two dates?

Question

I am trying to calculate the difference between two dates. This is what I'm currently using:

int currentyear = DateTime.Now.Year;

DateTime now = DateTime.Now;
DateTime then = new DateTime(currentyear, 12, 26);
TimeSpan diff = now - then;
int days = diff.Days;
label1.Text = days.ToString() + " Days Until Christmas";

All works fine except it is a day off. I am assuming this is because it does not count anything less than 24 hours a complete day. Is there a way to get it to do so? Thank you.

Solution 1

int days = (int)Math.Ceiling(diff.TotalDays);

Solution 2

The question is rather philosophic; if Christmas was tomorrow, would you consider it to be 1 day left, or 0 days left. If you put the day of tomorrow into your calculation, the answer will be 0.

Solution 3

Your problem goes away if you replace your:

DateTime.Now

with:

DateTime.Today

as your difference calculation will then be working in whole days.

Comments

[Rubens Farias]

Cannot implicitly convert type 'double' to 'int'. An explicit conversion exists (are you missing a cast?)

[user]

int days = Convert.ToInt32(Math.Ceiling(diff.TotalDays));

[LorenVS]

Oops, assumed Math.Ceiling returned int... kind of stupid now that I think about it

[user]

Any idea why it's returning a "-" before the number of days?

[user]

Oh wow, I feel dumb. Well I changed that and then it was returning the wrong value for the days, so I ended up using the int days = diff.Days; as I originally did.