A number of holidays move around from year to year. For example, in Canada Victoria day (aka the May two-four weekend) is the Monday before May 25th, or Thanksgiving is the 2nd Monday of October (in Canada).
I've been using variations on this Linq query to get the date of a holiday for a given year:
var year = 2011;
var month = 10;
var dow = DayOfWeek.Monday;
var instance = 2;
var day = (from d in Enumerable.Range(1,DateTime.DaysInMonth(year,month))
let sample = new DateTime(year,month,d)
where sample.DayOfWeek == dow
select sample).Skip(instance-1).Take(1);
While this works, and is easy enough to understand, I can imagine there is a more elegant way of making this calculation versus this brute force approach.
Of course this doesn't touch on holidays such as Easter and the many other lunar based dates.
And it gets complicated if you have to consider non-christian holidays. For example, jewish holidays are based on the jewish calender..
Maybe not so elegant, but more error prone - you can just add a table of all relevant holidays for the next 100 years.
int margin = (int)dow - (int)new DateTime(year, month, 1).DayOfWeek;
if (margin < 0) margin = 7 + margin;
int dayOfMonth = margin + 7*(instance - 1) //this is for 0-based day number, add 1 if you need 1-based. instance is considered to be 1-based
Please note that I wrote it without trying to compile, so it is to give the idea, but may require some clean up. Hope this helps!
Related
Respected all I want to bring data from a dated column with input of a Month like I have a column in database which type is dated but I want data only mentioning just month and year I tried but got errors please check my query
SELECT
M.INV_NUM, M.GD_NUM, M.INV_DATE, M.QTY1,
D.ITEM_CODE, D.HS_CODE, R.QNTY, R.waste_per,
R.WASTE_QNTY, (R.WASTE_QNTY+R.QNTY) TOTAL_CONSUMED
FROM
DOCT_EXPT_SALE_MST M,
DOCT_EXPT_SALE_RAW R,
DOCT_EXPT_SALE_DTL D
WHERE
R.SALE_DET_ID = D.SALE_DET_ID
AND D.SALE_ID = M.SALE_ID
AND M.INV_DATE BETWEEN TO_DATE(TRUNC('072022','MMYYYY')) AND TO_DATE(TRUNC('072022','MMYYYY'))--TO_NUMBER(TO_DATE(TO_CHAR('01072022','DDMMYYYY'))) AND TO_NUMBER(TO_DATE(TO_CHAR('31072022','DDMMYYYY')))
AND M.COMP_CODE = 3;
I tried many things but all is gone in vain. If anybody help me on this, I shall be very thankful my database is 11g
If you are being passed the string '072022' then you can do:
AND M.INV_DATE >= TO_DATE('072022','MMYYYY')
AND M.INV_DATE < ADD_MONTHS(TO_DATE('072022','MMYYYY'), 1)
The TO_DATE('072022','MMYYYY') clause will give you midnight on the first day of that month, so 2022-07-01 00:00:00.
The ADD_MONTHS(TO_DATE('072022','MMYYYY'), 1) clause will take that date and add one month, giving 2022-08-01 00:00:00.
The two comparisons will then find all dates in your column which are greater than or equal to 2022-07-01 00:00:00, and less that 2022-08-01 00:00:00 - which is all possible dates and times during that month.
So your query would be (switching to ANSI joins!):
SELECT
M.INV_NUM, M.GD_NUM, M.INV_DATE, M.QTY1,
D.ITEM_CODE, D.HS_CODE, R.QNTY, R.waste_per,
R.WASTE_QNTY, (R.WASTE_QNTY+R.QNTY) TOTAL_CONSUMED
FROM
DOCT_EXPT_SALE_MST M
JOIN
DOCT_EXPT_SALE_DTL D ON D.SALE_ID = M.SALE_ID
JOIN
DOCT_EXPT_SALE_RAW R ON R.SALE_DET_ID = D.SALE_DET_ID
WHERE
M.INV_DATE >= TO_DATE('072022','MMYYYY')
AND M.INV_DATE < ADD_MONTHS(TO_DATE('072022','MMYYYY'), 1)
AND M.COMP_CODE = 3;
I would like to know the time difference between two dates (Time/DateTime class) in days, i have one date created from the Date class and the other coming from my rails model, the one coming from the model is of the Time class, i want to know the number of days in between.
#current_day = Date.new
#created_day = establishment.created_at
i have tried getting this result using the days_ago function but it doesn't take into consideration the months.
old_date = Date.parse('2016-08-10')
new_date = Date.parse('2016-09-02')
days_between = (new_date - old_date).to_i
You have to convert days betweet to integer, because otherwise the result would be instance of Rational class.
Solution to your question after edit:
#current_day = Date.new
#created_day = establishment.created_at
days_between = (#current_day - #created_day.to_date).to_i
Solution to your question: Try this one it will work.
days_between = ("Tue Oct 24 09:20:25 UTC 2017".to_date.."Fri Oct 27 11:20:08 UTC 2017".to_date).count
If you print the result(days_between) you will get result as 4
I'm relatively new to VB6 and I've just been given an assignment where I have a date - for example '4/12/2016' - from this date, i'm trying to find out the day that it is. So let's say it's a wednesday. Now from this day, I'm trying to determine the dates for the week [sun(startdate) - sat(enddate)). How would I go about doing something like this?
EDIT: I have a pretty good idea about finding out the date for sunday and saturday, since I can simply do something along the lines...
dim dateStart,dateend as date
Ex of date given to me = '4/12/2016'
Dim dateDay as variant
dateDay = whatever I get here - i'm assuming that a date will return a number for whatever day it is ???? Not sure
Select Case dateDay
case 1 -Monday?
dateStart=dateadd("d",-1,'4/12/2016)
dateEnd = dateadd("d",6, '4/12/2016)
case 2 -Tuesday?
datestart = dateadd("d",-2,'4/12/2016)
dateend = dateadd("d",5,'4/12/2016)
End Select
Basically do the SELECT statement for all cases. Am I on the right track?
This code:
Debug.Print Format(DatePart("w", Now), "dddd")
will print whatever day of the week it is now to the Immediate window. If you want the abbreviated day of week, use "ddd" for the format.
Now, this code:
Dim DOW As String
Select Case DatePart("w", Now)
Case vbSunday
DOW = "Sunday"
Case vbMonday
DOW = "Monday"
Case vbTuesday
DOW = "Tuesday"
Case vbWednesday
DOW = "Wednesday"
Case vbThursday
DOW = "Thursday"
Case vbFriday
DOW = "Friday"
Case vbSaturday
DOW = "Saturday"
End Select
Debug.Print DOW
will do the same thing. However, it shows you how to evaluate programmatically which day of the week you're dealing with, by using vbSunday, vbMonday, etc. That should give you what you need to get started on your Select statement. To use your example, DatePart("w", "4/12/2016") evaluates to 3, or vbTuesday.
VB6 reference documentation is here, and rather well hidden I might add. Look up Format and DatePart to get familiar with other options.
EDIT: As MarkL points out, the Weekday function is available in VB6 (I thought it wasn't), and is simpler (one less argument) than using DatePart. This code:
Debug.Print Format(Weekday(Now), "dddd")
will also print whatever day of the week it is to the immediate window. jac has also provided a link to the Weekday function in the comments above.
You can try below codes, The code will return name of the day.
txtDateTime.Text = WeekdayName(Weekday(Now))
txtDateTime.Text = WeekdayName(Weekday(12 / 30 / 1995))
txtDateTime.Text = WeekdayName(Weekday(Date))
I need to know what date it is based on a week number and a day number.
So if I have weeknr=3 and day=1(for today- sunday) and lets say the year=2016 how can I make this into 2016-01-24.
Any input really appreciated, thanks.
Your best help will be the DatePart function (see here for docs). It's not altogether straightforward, because there are options to consider like "first day of week" and "first week of year", but you can define those in DatePart.
This would be my solution:
option explicit
function getDateByWeek(year, week, day)
dim dt, woy, add_days
dt = DateSerial(year, 1, 1)
do
woy = DatePart("ww", dt, vbSunday, vbFirstFullWeek)
' possibly change options [,firstdayofweek[,firstweekofyear]]
dt = DateAdd("d", 1, dt)
loop while woy<>1
add_days = week * 7 + day - 2
' -1 because we already added one day extra in the loop
' -1 to correct given day (sunday = 1)
getDateByWeek = DateAdd("d", add_days, dt)
end function
Response.Write "RESULT: " & getDateByWeek(2016, 3, 1) ' -> 24.01.2016
I start by finding the first day of the first week in a loop and then adding the cumulative amount of days to have a result.
Well the best way is to work out what the week start of the year is and take it from there.
Firstly, the first Thursday of any year is always in the first week of the year, so a simple calculation of adding the correct number onto the 1st January is obvious. After this we simply mulitply out the weeks and add the days:
Const C_THURSDAY = 5
Function GetDateFromYWD(y, w, d)
Dim tDate, aDate
'Get the first of the year...
tDate = DateSerial(y, 1, 1)
'Workout the start of the first week in the year...
aDate = tDate + Int(WeekDay(tDate)>C_THURSDAY And 7) - WeekDay(tDate)
'Add on the number of weeks plus days we're looking for...
aDate = aDate + (w * 7) + d
GetDateFromYWD = aDate
End Function
I made student list containing roll no.,name, gender, DOB,Age ,marks1,marks2,marks3,total and avg.
i want to right a code for age
that is when i click on age it should display the correct age according to the DOB given.
can you help using textbox events in c#
The algorithm should be
ageInYears = currentYear - birthYear - (birthMonth <= currentMonth && birthDay <= currentDay ? 0 : 1);
Subtract the years, and subtract an additional year if they haven't had their birthday yet this year.