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Finding a DateTime After a TimeSpan Ignoring Weekdays and holidays [duplicate]

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AddBusinessDays and GetBusinessDays
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Closed 3 years ago.
I am trying to calculate a finishing date when adding a duration to a start date, but skipping weekends and holidays:
DateTime start = DateTime.Now;
TimeSpan duration = TimeSpan.FromHours(100);
List<DateTime> = //List of holidays
DateTime end = ?
For example if it is 11pm on a Friday and I add 2 hours, it would end on 1am Monday morning.
Is there a neat way of doing this?
I have a temporary fix which increments the time by an hour and checks the day of the week, but it is very inefficient.
Original Idea (untested):
public static DateTime calEndDate(DateTime start, TimeSpan duration, List<DateTime> holidays)
{
var startDay = start.Day;
var i = 0;
var t = 0;
while (TimeSpan.FromHours(t) < duration)
{
var date = start.Add(TimeSpan.FromHours(i));
if (date.DayOfWeek.ToString() != "Saturday" && date.DayOfWeek.ToString() != "Sunday") //and something like !holidays.contains(start)
{
t++;
}
i++;
}
return start.Add(TimeSpan.FromHours(t));
}
}
However is needs to run over 100 times for different start dates/durations on one asp.net page load. I don't know how to benchmark it, but it doesn't seem like an elegant solution?

Here's an algorithm I'd try.
I'm on my phone, and I'll get it wrong, but you should see the logic...
var end = start;
var timeToMidnight = start.Date.AddDays(1) -start;
if ( duration < timeToMidnight ) return start + duration;
end = endMoment + timeToMidnight;
duration = duration - timeToMidnight;
//Helper method
bool IsLeisure(Datetime dt) => (dt.DayOfWeek == DayOfWeek.Saturday) || (dt.DayOfWeek == DayOfWeek.Sunday) || holidays.Any( h => h.Date == dt.Date);
//We're at the first tick of the new day. Let's move to a work day, if needed.
while(IsLeisure(end)) { end = end.AddDays(1); };
//Now let's process full days of 'duration'
while(duration >= TimeSpan.FromDays(1) ) {
end = end.AddDays(1);
if(!IsLeisure(end)) duration = duration - TimeSpan.FromDays(1);
}
//Finally, add the reminder
end = end + duration;
Note: you haven't specified the logic for when start moment is a weekend or a holiday.

Yes there is :
DateTime currentT = DateTime.Now;
DateTime _time_ = currentTime.AddHours(10);
Simple and neat.

DateTime un-representable error in C#

I have to add 15 minutes to the current time and set it to a DateTime object in C#. If my current time is say 11:50 PM, and 15 minutes is added, the hour part becomes 24 and is causing the following error: "Hour, Minute, and Second parameters describe an un-representable DateTime."
public static DateTime NewTime(this DateTime dateTime)
{
int hour = dateTime.Hour;
int minute = dateTime.Minute;
if (minute > 0)
{
minute = dateTime.Minute + (15);
if (minute >= 60)
{
hour = hour + 1;
minute = 0;
}
}
return new DateTime(dateTime.Year, dateTime.Month,
dateTime.Day, hour, minute, 0);
}
Thanks

Your logic does not make sense, you are only adding minutes if the minutes are greater than 0 so what happens if they are 0?
To add time use the methods built into the type definition, no need to reinvent the wheel. Example:
public static DateTime Add15Minutes(this DateTime dateTime)
{
return dateTime.AddMinutes(15);
}

You are checking for an overflow on the minute attribute, but not the hour attribute. You could check for an overflow on the hour attribute like this:
public static DateTime NewTime(this DateTime dateTime)
{
int hour = dateTime.Hour;
int minute = dateTime.Minute;
var day = dateTime.Day;
if (minute > 0)
{
minute = dateTime.Minute + (15);
if (minute >= 60)
{
hour = hour + 1;
minute = 0;
}
}
if (hour > 24) {
day += 1;
}
return new DateTime(dateTime.Year, dateTime.Month,
day, hour, minute, 0);
}
However, you will also run into problems with the overflow of days in a month, which is even more complicated to handle. Instead, just use the built in Add function:
public static DateTime NewTime(this DateTime dateTime)
{
return new dateTime.AddMinutes(15);
}

I think you are overthinking this maybe? DateTime already provides many support methods and this will probably do what you need without the need to create an extension method:
var myValue = new DateTime(2017,3,14,23,50,0);
var result = myValue.AddMinutes(15);

Time range is invalid statement

I am trying to create an if statement based on the dropdown created below. That determines whether the Time from is before or after Time To. According to the results, show validation.
For Example: Time From 4:00 and Time To 4:30. Should be acceptable.
However if Time From 4:00 and Time To 3:30. This should not be acceptable.
Any ideas?
private void BindTime()
{
// Set the start time (00:00 means 12:00 AM)
DateTime StartTime = DateTime.ParseExact("00:00", "HH:mm", null);
// Set the end time (23:55 means 11:55 PM)
DateTime EndTime = DateTime.ParseExact("23:55", "HH:mm", null);
//Set 15 minutes interval
TimeSpan Interval = new TimeSpan(0, 15, 0);
//To set 1 hour interval
//TimeSpan Interval = new TimeSpan(1, 0, 0);
ddlTimeFrom.Items.Clear();
ddlTimeTo.Items.Clear();
while (StartTime <= EndTime)
{
ddlTimeFrom.Items.Add(StartTime.ToShortTimeString());
ddlTimeTo.Items.Add(StartTime.ToShortTimeString());
StartTime = StartTime.Add(Interval);
}
ddlTimeFrom.Items.Insert(0, new ListItem(" Select ", "0"));
ddlTimeTo.Items.Insert(0, new ListItem(" Select ", "0"));
}

When you want to validate, use this function:
private bool IsSelectionValid()
{
DateTime fromTime;
DateTime toTime;
if(!DateTime.TryParse(ddlTimeFrom.SelectedValue, out fromTime) ||
!DateTime.TryParse(ddlTimeTo.SelectedValue, out toTime))
{
return false;
}
return fromTime < toTime;
}
IsSelectionValid would give return false if fromTime is not less than toTime.

Finding deltatime in C# using stopwatch

I'm trying to write a fixed timestep.
Stopwatch timer = Stopwatch.StartNew();
TimeSpan dt = TimeSpan.FromSeconds(1/50);
TimeSpan elapsedTime = TimeSpan.Zero;
while(window.IsOpen())
{
timer.Restart();
elapsedTime = timer.Elapsed;
while(elapsedTime > dt)
{
window.DispatchEvents();
elapsedTime -= dt;
gameObject.FixedUpdate(deltaTime goes here as double);
}
}
I want to pass dt as argument to FixedUpdate as a double, is there a way to convert it somehow?
I'm also not quite sure about this line TimeSpan dt = TimeSpan.FromSeconds(1/50); Basically I want dt to hold 1/50th of a second.

Regarding this part TimeSpan.FromSeconds(1/50). TimeSpan.FromSeconds accepts double, 1/50 is int(int/int gives int w/o floating point part), and its value is equal to 0, when passed to method this values gets implicitly converted to double and eventually you get: TimeSpan.FromSeconds(1/50) -> 00:00:00
To make it right, you have to work with double from the beginning and use 1.0/50(1.0 is double):
TimeSpan.FromSeconds(1.0/50) -> 00:00:00.0200000
Regarding this one: gameObject.FixedUpdate(deltaTime goes here as double);
I assume you want to pass milliseconds as and argument value. For that you can write:
gameObject.FixedUpdate(dt.TotalMilliSeconds);

Without knowing the internals of FixedUpdate, you probably want TotalMilliseconds.
Stopwatch timer = Stopwatch.StartNew();
TimeSpan dt = TimeSpan.FromSeconds(1.0/50.0);
TimeSpan elapsedTime = TimeSpan.Zero;
while(window.IsOpen())
{
timer.Restart();
elapsedTime = timer.Elapsed;
while(elapsedTime > dt)
{
window.DispatchEvents();
elapsedTime -= dt;
gameObject.FixedUpdate(dt.TotalMilliseconds);
}
}

C# Timer counter in xx.xx.xx format

I have a counter that counts up every 1 second and add 1 to an int.
Question
How can I format my string so the counter would look like this:
00:01:23
Instead of:
123
Things I've tried
Things I've tried so far:
for (int i = 0; i < 1; i++)
{
_Counter += 1;
labelUpTime.Text = _Counter.ToString();
}
My timer's interval is set to: 1000 (so it adds 1 every second).
I did read something about string.Format(""), but I don't know if it is applicable.
Thanks if you can guide me through this :D!

Use a TimeSpan:
_Counter += 1;
labelUpTime.Text = TimeSpan.FromSeconds(_Counter).ToString();

You could make it a TimeSpan (for that's what it is, a span of time), then format that:
labelUpTime.Text = TimeSpan.FromSeconds(_Counter).ToString();

Don't use a counter, and don't rely on the timer firing exactly every second. It won't. Do something like this.
class TimerTest
{
private DateTime _start = DateTime.Now;
private Timer _timer = new Timer(1000);
public TimerTest()
{
// (DateTime.Now - _start) returns a TimeSpan object
// Default TimeSpan.ToString() returns 00:00:00
_timer.Elapsed = (o, e) => labelUpTime.Text = (DateTime.Now - _start).ToString();
}
}
You can adjust the formatting with the TimeSpan.ToString method.

TimeSpan timer = new TimeSpan(0);
and on your interval:
timer += TimeSpan.FromSeconds(1);

Use timespan. To add a second use
mytimespan.Add(new TimespanFromSeconds(1));
Console.WriteLine(mytimespan); //Output in the form of xx:xx:xx
http://www.dotnetperls.com/timespan

it worked well for me
public TimeSpan ElapsedTimeFormatted
{
get
{
if (FinishedOn != null &&
StartedAt != null)
{
TimeSpan durationCount = new TimeSpan();
int hours = 0;
int minutes = 0;
int seconds = 0;
var times = Segments.Select(c => c.ElapsedTimeFormatted).ToList();
foreach (var time in times)
{
TimeSpan timeParse = TimeSpan.Parse(time);
hours = hours + (int)timeParse.Hours;
minutes = minutes + (int)timeParse.Minutes;
seconds = seconds + (int)timeParse.Seconds;
durationCount = new TimeSpan(hours, minutes, seconds);
}
return durationCount;
}
return new TimeSpan();
}
}