Ask Ben: Shifting ColdFusion's DayOfWeek() Functionality
Posted May 8, 2007 at 5:48 PM by Ben Nadel
Macbuoy, in one of his comments, asked about shifting the day of the week functionality that ColdFusion provides. By default, ColdFusion assigns Sunday as day One and Saturday as day Seven. To shift this value, such as having Monday be day One and having Sunday be day Seven, requires wrapping ColdFusion's DayOfWeek() method in a custom, user defined function:
- <cffunction
- name="MyDayOfWeek"
- access="public"
- returntype="numeric"
- output="false"
- hint="Returns our proxy day of week value.">
-
- <!--- Define arguments. --->
- <cfargument
- name="Date"
- type="date"
- required="true"
- hint="The date that we are using to get the day of week."
- />
-
- <cfargument
- name="FirstDayOfWeek"
- type="numeric"
- required="false"
- default="2"
- hint="This is the day (1 = Sunday) that we are treating as the first day of the week."
- />
-
-
- <!---
- Translate the actual day of the week to the pseudo
- day of the week using the passed in FirstDayOfWeek.
- --->
- <cfreturn
- (
- (
- (
- DayOfWeek( ARGUMENTS.Date ) +
- (7 - ARGUMENTS.FirstDayOfWeek)
- ) MOD 7
- ) +
- 1
- ) />
- </cffunction>
This ColdFusion user defined function takes an optional argument, FirstDayOfWeek, which will define which day is the first day of the week. It defaults to 2 which defines Monday as day One, but this can be any value between 1 and 7 (I am not doing any error checking on that).
To test, let's run over two weeks worth of dates to see how this ColdFusion user defined function translates the original DayOfWeek() to our business-related day of week:
- <!---
- Loop over every day in these two weeks to
- demonstrate translated days of the week.
- --->
- <cfloop
- index="dtDay"
- from="05/06/2007"
- to="05/19/2007"
- step="1">
-
- #DateFormat( dtDay )# -
- #DayOfWeek( dtDay )#
-
- -to-
-
- <!--- Use translated DayOfWeek(). --->
- #MyDayOfWeek( dtDay )#
-
- <br />
-
- </cfloop>
This gives us the following output:
06-May-07 - 1 -to- 7
07-May-07 - 2 -to- 1
08-May-07 - 3 -to- 2
09-May-07 - 4 -to- 3
10-May-07 - 5 -to- 4
11-May-07 - 6 -to- 5
12-May-07 - 7 -to- 6
13-May-07 - 1 -to- 7
14-May-07 - 2 -to- 1
15-May-07 - 3 -to- 2
16-May-07 - 4 -to- 3
17-May-07 - 5 -to- 4
18-May-07 - 6 -to- 5
19-May-07 - 7 -to- 6
As you can see, we are successfully translating Monday (day 2) as the first day of the week.
Reader Comments
good work, this should really have been an optional parameter to the function in the first place. CF's default to Sunday for the first day of the week isn't logical, especially for us in the UK. It's also against ISO 8601.
http://en.wikipedia.org/wiki/ISO_8601
How is it in the UK? Is Monday the first calendar day over there?
yes indeed.
I'm not sure if I'm doing something wrong, but when I apply this to my version of your most recent Month calendar, I'm getting dates misaligned with day of week. I'm going to start from scratch with your example and add the new wrapper and see how it turns out.
Will report.
Interesting. I did not try applying it to the calendar. I will give it a go at lunch, see what I can come up with.
yeah. When I apply this to this:
http://www.bennadel.com/index.cfm?dax=blog:663.view
calendar grid alignment is off. my first guess is that I'm applying the wrapper too often. . .I need to understand the MyDayOfWeek math better to do this right.
@Macbuoy,
Check this out:
http://www.bennadel.com/index.cfm?dax=blog:693.view
You're probably making a small mistake somewhere. This took practically no changes. I just replaced the DayOfWeek() calls and reordered the calendar header.
If you take a look at the calendar I am interested in the members of the club to be able to submit a post and it appears on the day instead of a click into. I am not sure if that is what yours does because the demo will not allow add/submit?
