I have a collection of dates that are business days and I have a Start Date. When I add a TimeSpan to the Start Date DateTime I have to ensure that when adding the days in TimeSpan, I skip over holidays. Any suggestions on how I can do this?
You add the timespan as it is. When that is done, you iterate search for dates in your collection that falls between the original date and the new date. For each time you encounter for each hit you add another day to the new date, and repeat until you are through your collection of dates. This can be optimized if your datecollection is sorted.
You need to take into account how many non-business days there are in any added date range.
In a 20 day range, there may be 6 non-business days.
You can't just add this number of days to the last day because the new date range may contain non-business days too. You have to add the days, and then figure out how many of those days you've added are also holidays:
Here's some non-tested pcode
Add Timespan to date (DateIn,timespan)
finalDateTime = (fromDate + timespan)
fromDate = DateIn.date
toDate = finalDateTime.date
repeat
iDays = GetHolidaysBetween (fromDate, toDate)
finalDateTime = (finalDateTime + iDays)
fromDate = (toDate+1)
toDate = (toDate+iDays)
until (iDays=0)
return finalDateTime
end_function
What about something like this?
public DateTime AddBusinessDays(List<DateTime> businessDays, DateTime startDate, TimeSpan span)
{
// Add the initial timespan
DateTime endDate = startDate.Add(span);
// Calculate the number of holidays by taking off the number of business days during the period
int noOfHolidays = span.Days - businessDays.Where(d => d >= startDate && d <= endDate).Count();
// Add the no. of holidays found
endDate.AddDays(noOfHolidays);
// Skip the end date if it lands on a holiday
while (businessDays.Contains(endDate))
endDate = endDate.AddDays(1);
return endDate;
}
Related
I am given two dates as strings like this:
Beginning month: 10
Beginning year: 2010
Ending month: 01
Ending Year 2020
I want to query my entity and get everything that is equal or between these ranges.
So, I want everything from 10/2010 to 01/2020.
I have this code and I got stuck on how to convert the date correctly and the comparison:
dollartotals = (from x in se.AchBatches
where x.CompanyCode == company &&
DbFunctions.TruncateTime(x.DateTimeSubmitted) >=
// stuck here
select x.DollarTotal).Sum();
How do I handle the individual month/year strings and make a date comparison without a day?
Thanks for any assistance!
You want to check against the actual datetime submitted, not a truncated version of it.
The key is to build actual datetimes in advance, then just do a regular date window check.
Assume you have four strings as listed in your question:
//you might use TryConvert or a Try block here to validate your string data...
int beginYear = Integer.Convert(strBeginYear);
int beginMonth = Integer.Convert(strBeginMonth);
int endYear = Integer.Convert(strEndYear);
int endMonth = Integer.Convert(strEndMonth);
DateTime start = new DateTime(beginYear, beginMonth, 1);
DateTime endLimit = new DateTime(endYear, endMonth, 1).AddMonths(1);
dollartotals = (from x in se.AchBatches
where x.CompanyCode == company &&
x.DateTimeSubmitted >= start &&
x.DateTimeSubmitted < endLimit
select x.DollarTotal).Sum();
I want everything from 10/2010 to 01/2020.
Not sure if you want a DateTime sequence with every Tick between those dates, or every second, or every Day. Let's assume you want every Day: All Days from startDate.Date until and inclusive endDate.Date.
I use StartDate.Date, so if StartDate is 2020-02-05 13:20:14, then you still get February 5th 2020 at 00:00:00
IEnumerable<DateTime> GetDateRange(DateTime startDate, DateTime endDate)
{
DateTime lastDate = endDate.Date;
DateTime date = startDate.Date;
while (date <= lastDate)
{
yield return date;
date = date.AddDays(+1);
}
}
Usage:
var allDaysOfFebruary2020 = GetDateRange(new DateTime(2020, 01, 01),
new DateTime(2020, 02, 29));
You'll get the sequence from 1st February 2020 until and inclusive 29th February 2020.
I know this topic has already been discussed but I want to add days to only date, not the complete datetime and then I need to subtract it with date. What I have done till now is :
string endDate = DateTime.Now.AddDays(2).ToShortDateString();
Now this gives me string like 19-jan-17 which is great but when I want to subtract it with todays date, it gives error because the end date is in string. I tried below code:
TimeSpan diff = DateTime.Now.ToShortDateString() - endDate ;
or
TimeSpan diff = DateTime.Now.ToShortDateString() - Convert.ToDateTime(endDate)
or
TimeSpan diff = DateTime.Now.ToShortDateString() - Convert.ToString(endDate)
and if I change DateTime.Now.ToShortDateString() to DateTime.Now then it will also include time which I do not want. I just want to add days in date only and then subtract it with today's date.
Any suggestions. Please help.
Try this:
DateTime endDate = DateTime.Today.AddDays(2);
TimeSpan diff = DateTime.Today - endDate
The Today property will return only the date part (so time will be 00:00:00), but still in a DateTime struct, so you can get a TimeSpan from subtracting another DateTime from it.
Did you try doing the following?
string endDate = DateTime.Now.Date.AddDays(2);
Still, it is not clear why you have to do that. A bit of context would be great for proposing other solutions.
I join Federico, you need to use the Date property of the DateTime instance. It will return the 00:00:00 moment of the date.
One side note:
Just keep all dates in DateTime (e.g. do not convert them into strings) before calculating the diff.
e.g.:
TimeSpan diff = DateTime.Now.Date - endDate;
If you need the date part, you can use format strings after the calculation.
e.g.:
endDate.ToString("yyyy.MM.dd")
Hi I'm trying to capture two dates selected by the user in a C# Calendar Control and I want the date range to be displayed in a label. I have worked out on the following code but it generates a Minus value ; not the actual date range.
DateTime from = CalFrom.SelectedDate;
DateTime to = CalTo.SelectedDate;
double days = (CalTo.SelectedDate - CalFrom.SelectedDate).TotalDays;
TimeSpan t = to - from;
double noOfDays = t.TotalDays;
TimeSpan ts = to - from;
double differnceindays = ts.TotalDays;
lblNoofDays.Text = differnceindays.ToString();
This code is working perfectly for me for calculating the number the days between two days.
DateTime d1 = DateTime.Now;
DateTime d2 = DateTime.Now.AddDays(10);
TimeSpan difference = d2 - d1;
var days = difference.TotalDays;
DateTime.Now.Subtract(startDate).Days.ToString();
try to calculate no of days between two dates
string days = (date2 - date1).Value.Days.ToString();
The only problem I see is that you assume the start and end dates will be correctly range checked, meaning start date is never greater than end date (which would produce negative values for total days). If you want to correct for the fact that start date may be after end date, then this should work.
DateTime startDate = DateTime.Now.AddDays(-94); // Example random 94 day span..
DateTime endDate = DateTime.Now;
TimeSpan duration = endDate > startDate ? endDate - startDate : startDate - endDate;
double daysBetweenDates = duration.TotalDays;
Note: "daysBetweenDates" will include fractional days (thus the double type). Also, the code above assumes local time. If you want UTC you will need to account for that.
i am doing a project on cab services.in this rate is different for day and night.
in the form only journey start date and end date is selected.based on this i have to calculate the no of days and nights.
here i am confused how to calculate the no of days and night.
thanks in advance.
private List<DateTime> GetDateRange(DateTime StartingDate, DateTime EndingDate)
{
if (StartingDate > EndingDate)
{
return null;
}
List<DateTime> rv = new List<DateTime>();
DateTime tmpDate = StartingDate;
do
{
rv.Add(tmpDate);
tmpDate = tmpDate.AddDays(1);
} while (tmpDate <= EndingDate);
return rv;
}
To view this code in action, copy and paste the following code into SnippetCompiler:
DateTime StartingDate = DateTime.Parse("02/25/2007");
DateTime EndingDate = DateTime.Parse("03/06/2007");
foreach (DateTime date in GetDateRange(StartingDate,EndingDate))
{
WL(date.ToShortDateString());
}
Sample output :
2/25/2007
2/26/2007
2/27/2007
2/28/2007
3/1/2007
3/2/2007
3/3/2007
3/4/2007
3/5/2007
3/6/2007
Use the Subtract method to get the difference, which is a TimeSpan value. Example:
TimeSpan diff = SecondDate.Subtract(FirstDate);
You can get the length of the time span for example in hours:
double hours = diff.TotalHours;
I'm not sure which time unit "days and nights" could be interpreted as, though. Perhaps days?
double days = diff.TotalDays;
DateTime dt1,dt2;
//...
TimeSpan period = dt1 - dt2;
int days = period.Days;
It sounds like a very long Cab journey that takes days and nights!
I think you need to define what a day and a night is more clearly in order to get your perfect answer. You also need to think about what impact Daylight Saving Time has on your calculations.
If say:
a day was the period from 6am to 6pm
the night was the rest - from 6pm to 6am
and you wanted to really count hours rather than days
In this case then a calculation would require you to:
iterate a currentDateTime from the startDateTime to the endDateTime
choose the increment in the currentDateTime so that it jumps to the next time barrier (6am, 6pm or the endDateTime)
within each loop, then add to your cumulative calculation of numDayHours or numNightHours so far.
Note that:
you could make this calculation quicker by counting whole days along the way
you need to be very careful about the time zone you are calculating in (I just hope that your taxi doesn't cross time zone boundaries!)
you need to be very careful about local time changes - especially "daylight savings time" type changes - the duration from 6pm to 6am is not always 12 hours!
Some pseudo code:
var numDayHours = 0.0;
var numNightHours = 0.0;
var current = startDateTime;
while (current < endDateTime)
{
next_hop = calculate_next_hop (current, endDateTime);
// select next date time
switch (next_hop.hop_type)
{
case HopType.night_time_hop:
numNightHours += next_hop.num_hours;
break;
case HopType.day_time_hop:
numDayHours += next_hop.num_hours;
break;
}
current = next_hop.EndDateTime;
}
// and here is the result
double numDays = numDayHours / 12.0;
double numHours = numNightHours / 12.0;
How to subtract a year from current datetime using c#?
var myDate = DateTime.Now;
var newDate = myDate.AddYears(-1);
DateTime oneYearAgoToday = DateTime.Now.AddYears(-1);
Subtracting a week:
DateTime weekago = DateTime.Now.AddDays(-7);
It might be worth noting that the accepted answer may adjust the date by either 365 days or 366 days due to leap years (it gets the date for the same day of the month one year ago, with the exception of 29th February where it returns 28th February).
In the vast majority of cases this is exactly what you want however if you are treating a year as a fixed unit of time (e.g. the Julian year) then you would need to subtract from either days;
var oneFullJulianYearAgo = DateTime.Now.AddDays(-365.25);
or seconds;
var oneFullJulianYearAgo = DateTime.Now.AddSeconds(-31557600);