I want to count number of days using two datetime picker. Please take a look the picture below.

But, if you can see the image below., they counting number of days PER DAY,

that’s why the total number of days display is equal to 2 days.

instead of one day, because of time.

I have a code to count number of day

DateTime dt1 = dtpckerPickupDate.Value;
DateTime dt2 = dtpckerReturnDate.Value;
TimeSpan t = dt2 - dt1;

double dDays = t.TotalDays;
//int days = Convert.ToInt32(dDays);
int PlusOneDay = Convert.ToInt32(dDays + 1);//if counting included today

txtNumOfDays.Text = PlusOneDay.ToString() + " Days";