I want to increase time to current time.
for example, I have the time of the problem and the expected time to complete them
How can I add?
(Date
You can use other variable
DateTime otherDate = DateTime.Now.AddMinutes(25);
DateTime tomorrow = DateTime.Now.AddHours(25);
You can use the operators +
, -
, +=
, and -=
on a DateTime with a TimeSpan argument.
DateTime myDateTime = DateTime.Parse("24 May 2009 02:19:00");
myDateTime = myDateTime + new TimeSpan(1, 1, 1);
myDateTime = myDateTime - new TimeSpan(1, 1, 1);
myDateTime += new TimeSpan(1, 1, 1);
myDateTime -= new TimeSpan(1, 1, 1);
Furthermore, you can use a set of "Add" methods
myDateTime = myDateTime.AddYears(1);
myDateTime = myDateTime.AddMonths(1);
myDateTime = myDateTime.AddDays(1);
myDateTime = myDateTime.AddHours(1);
myDateTime = myDateTime.AddMinutes(1);
myDateTime = myDateTime.AddSeconds(1);
myDateTime = myDateTime.AddMilliseconds(1);
myDateTime = myDateTime.AddTicks(1);
myDateTime = myDateTime.Add(new TimeSpan(1, 1, 1));
For a nice overview of even more DateTime manipulations see THIS
Please note that you may add - (minus) sign to find minutes backwards
DateTime begin = new DateTime();
begin = DateTime.ParseExact("21:00:00", "H:m:s", null);
if (DateTime.Now < begin.AddMinutes(-15))
{
//if time is before 19:45:00 show message etc...
}
and time forward
DateTime end = new DateTime();
end = DateTime.ParseExact("22:00:00", "H:m:s", null);
if (DateTime.Now > end.AddMinutes(15))
{
//if time is greater than 22:15:00 do whatever you want
}
You can also add a TimeSpan to a DateTime, as in:
date + TimeSpan.FromHours(8);