How to find out a week of the day in C#?

[purkka]

Hi

I did not find any solution from Internet how to do it. There is a lot of
samples how to retrieve day of the week, but not number of the week.

With rgds

MP

[Joseph Byrns]

would this do what you want?:

Dim theDate as DateTime = DateTime.Now
Dim WeekOfYear as integer = Math.Ceiling(th eDate.DayOfYear / 7)

"purkka" <pu****@discuss ions.microsoft. com> wrote in message
news:45******** *************** ***********@mic rosoft.com...

Hi

I did not find any solution from Internet how to do it. There is a lot of
samples how to retrieve day of the week, but not number of the week.

With rgds

MP

[Wessel Troost]

Try this:

System.Globaliz ation.CultureIn fo myCI = new CultureInfo("en-US");
myCI.Calendar.G etWeekOfYear( DateTime.Now,
System.Globaliz ation.CalendarW eekRule.FirstFo urDayWeek,
System.DayOfWee k.Sunday );

Greetings,
Wessel

-----Original Message-----
From: purkka [mailto:pu****@d iscussions.micr osoft.com]
Posted At: Monday, April 11, 2005 1:02 PM
Posted To: microsoft.publi c.dotnet.framew ork.aspnet
Conversation: How to find out a week of the day in C#?
Subject: How to find out a week of the day in C#?

Hi

I did not find any solution from Internet how to do it. There is a lot
of
samples how to retrieve day of the week, but not number of the week.

With rgds

MP

[purkka]

Hoops

Sorry. I did not mentioned, that my ASP.NET application fetch datevalues
(1/2/2005, 11/2/2005...) from Access db. Values are shown as a list in a
datagrid which should also provide week numbers like this:

Week Date Name .....
-------------------------------
15 12.4.2005 John Smith .....

With rgds
MP

"Wessel Troost" wrote:

Try this:

System.Globaliz ation.CultureIn fo myCI = new CultureInfo("en-US");
myCI.Calendar.G etWeekOfYear( DateTime.Now,
System.Globaliz ation.CalendarW eekRule.FirstFo urDayWeek,
System.DayOfWee k.Sunday );

Greetings,
Wessel

-----Original Message-----
From: purkka [mailto:pu****@d iscussions.micr osoft.com]
Posted At: Monday, April 11, 2005 1:02 PM
Posted To: microsoft.publi c.dotnet.framew ork.aspnet
Conversation: How to find out a week of the day in C#?
Subject: How to find out a week of the day in C#?

Hi

I did not find any solution from Internet how to do it. There is a lot
of
samples how to retrieve day of the week, but not number of the week.

With rgds

MP

[Juan T. Llibre]

Simen Sandelien wrote this nifty code to do just that :

private int WeekNumber_Enti re4DayWeekRule( DateTime date)
{

const int JAN = 1;
const int DEC = 12;
const int LASTDAYOFDEC = 31;
const int FIRSTDAYOFJAN = 1;
const int THURSDAY = 4;
bool ThursdayFlag = false;

int DayOfYear = date.DayOfYear;

int StartWeekDayOfY ear =
(int)(new DateTime(date.Y ear, JAN, FIRSTDAYOFJAN)) .DayOfWeek;
int EndWeekDayOfYea r =
(int)(new DateTime(date.Y ear, DEC, LASTDAYOFDEC)). DayOfWeek;

StartWeekDayOfY ear = StartWeekDayOfY ear;
EndWeekDayOfYea r = EndWeekDayOfYea r;
if( StartWeekDayOfY ear == 0)
StartWeekDayOfY ear = 7;
if( EndWeekDayOfYea r == 0)
EndWeekDayOfYea r = 7;

int DaysInFirstWeek = 8 - (StartWeekDayOf Year );
int DaysInLastWeek = 8 - (EndWeekDayOfYe ar );

if (StartWeekDayOf Year == THURSDAY || EndWeekDayOfYea r == THURSDAY)
ThursdayFlag = true;

int FullWeeks = (int) Math.Ceiling((D ayOfYear - (DaysInFirstWee k))/7.0);

int WeekNumber = FullWeeks;

if (DaysInFirstWee k >= THURSDAY)
WeekNumber = WeekNumber +1;

if (WeekNumber > 52 && !ThursdayFlag)
WeekNumber = 1;

if (WeekNumber == 0)
WeekNumber = WeekNumber_Enti re4DayWeekRule(
new DateTime(date.Y ear-1, DEC, LASTDAYOFDEC));
return WeekNumber;
}
If you want to read the comments to the code,
see http://konsulent.sandelien.no/VB_help/Week/

I edited them out so the post would be shorter.
If you could use Visual Basic, you could simply do :

<%
Response.Write( "This is this year's week number " & DatePart(DateIn terval.WeekOfYe ar,Date.Today,v bUseSystemDayOf Week,vbFirstJan 1) & ".")
%>

Maybe you could simply compile an assembly in VB.NET
which sets the week number, and call it from C#.

That seems a lot simpler than using the convoluted C# function quoted above.

Juan T. Llibre
ASP.NET MVP
http://asp.net.do/foros/
Foros de ASP.NET en Español
Ven, y hablemos de ASP.NET...
=============== =======

"purkka" <pu****@discuss ions.microsoft. com> wrote in message news:45******** *************** ***********@mic rosoft.com...

Hi

I did not find any solution from Internet how to do it. There is a lot of
samples how to retrieve day of the week, but not number of the week.

With rgds

MP

[Juan T. Llibre]

That code will produce output errors,
as the result is not compatible with ISO 8601.

See http://konsulent.sandelien.no/VB_help/Week/


Juan T. Llibre
ASP.NET MVP
http://asp.net.do/foros/
Foros de ASP.NET en Español
Ven, y hablemos de ASP.NET...
=============== =======

"Joseph Byrns" <jo*********@nn oossppaamm-yahoo.com> wrote in message
news:eM******** ******@tk2msftn gp13.phx.gbl...

would this do what you want?:

Dim theDate as DateTime = DateTime.Now
Dim WeekOfYear as integer = Math.Ceiling(th eDate.DayOfYear / 7)

"purkka" <pu****@discuss ions.microsoft. com> wrote in message
news:45******** *************** ***********@mic rosoft.com...

Hi

I did not find any solution from Internet how to do it. There is a lot of
samples how to retrieve day of the week, but not number of the week.

With rgds

MP

[Juan T. Llibre]

I should have added that this similar function
would be incorrect for the same reason :

System.DateTime dt = System.DateTime .Now;
int dayOfYear = dt.DayOfYear;
Label1.Text =
dayOfYear.ToStr ing()+":"+(((da yOfYear%7)==0)? (dayOfYear/7):(dayOfYear/7)+1).ToString( );

Juan T. Llibre
ASP.NET MVP
http://asp.net.do/foros/
Foros de ASP.NET en Español
Ven, y hablemos de ASP.NET...
=============== =======

"Joseph Byrns" <jo*********@nn oossppaamm-yahoo.com> wrote in message
news:eM******** ******@tk2msftn gp13.phx.gbl...

would this do what you want?:

Dim theDate as DateTime = DateTime.Now
Dim WeekOfYear as integer = Math.Ceiling(th eDate.DayOfYear / 7)

"purkka" <pu****@discuss ions.microsoft. com> wrote in message
news:45******** *************** ***********@mic rosoft.com...

Hi

I did not find any solution from Internet how to do it. There is a lot of
samples how to retrieve day of the week, but not number of the week.

With rgds

MP

[Wessel Troost]

If you're fetching the dates from SQL, you can try something like:

SELECT DATEPART('wk', YourDateField) As Week FROM YourTable

This works on SQL Server, not sure if it works with an Access backend.
This method always returns US weeknumbers.

Regards,
Wessel

-----Original Message-----
From: purkka [mailto:pu****@d iscussions.micr osoft.com]
Posted At: Monday, April 11, 2005 1:43 PM
Posted To: microsoft.publi c.dotnet.framew ork.aspnet
Conversation: How to find out a week of the day in C#?
Subject: Re: How to find out a week of the day in C#?

Hoops

Sorry. I did not mentioned, that my ASP.NET application fetch datevalues

(1/2/2005, 11/2/2005...) from Access db. Values are shown as a list in
a
datagrid which should also provide week numbers like this:

Week Date Name .....
-------------------------------
15 12.4.2005 John Smith .....

With rgds
MP

"Wessel Troost" wrote:

Try this:

System.Globaliz ation.CultureIn fo myCI = new CultureInfo("en-US");
myCI.Calendar.G etWeekOfYear( DateTime.Now,
System.Globaliz ation.CalendarW eekRule.FirstFo urDayWeek,
System.DayOfWee k.Sunday );

Greetings,
Wessel

-----Original Message-----
From: purkka [mailto:pu****@d iscussions.micr osoft.com]
Posted At: Monday, April 11, 2005 1:02 PM
Posted To: microsoft.publi c.dotnet.framew ork.aspnet
Conversation: How to find out a week of the day in C#?
Subject: How to find out a week of the day in C#?

Hi

I did not find any solution from Internet how to do it. There is a lot
of
samples how to retrieve day of the week, but not number of the week.

With rgds

MP

[Juan T. Llibre]

Simen Sandelien says ( Simen says? ) that will
produce results incompatible with ISO 8601

http://konsulent.sandelien.no/VB_help/Week/

He has this to say about that :

"My conclusion is that the builtin .NET FourDayWeekRule
and the GetWeekOfYear() method do NOT produce
week numbers according to ISO 8601."

Juan T. Llibre
ASP.NET MVP
http://asp.net.do/foros/
Foros de ASP.NET en Español
Ven, y hablemos de ASP.NET...
=============== =======

"Wessel Troost" <no*****@like.t he.sun> wrote in message
news:uv******** ******@TK2MSFTN GP14.phx.gbl...

Try this:

System.Globaliz ation.CultureIn fo myCI = new CultureInfo("en-US");
myCI.Calendar.G etWeekOfYear( DateTime.Now,
System.Globaliz ation.CalendarW eekRule.FirstFo urDayWeek,
System.DayOfWee k.Sunday );

Greetings,
Wessel

-----Original Message-----
From: purkka [mailto:pu****@d iscussions.micr osoft.com]
Posted At: Monday, April 11, 2005 1:02 PM
Posted To: microsoft.publi c.dotnet.framew ork.aspnet
Conversation: How to find out a week of the day in C#?
Subject: How to find out a week of the day in C#?

Hi

I did not find any solution from Internet how to do it. There is a lot
of
samples how to retrieve day of the week, but not number of the week.

With rgds

MP

[purkka]

Thanks for your reply. That was not help me out, but Juan T. Llibre's one
did. Your tip is useful as well.

Rgds MP

"Wessel Troost" wrote:

If you're fetching the dates from SQL, you can try something like:

SELECT DATEPART('wk', YourDateField) As Week FROM YourTable

This works on SQL Server, not sure if it works with an Access backend.
This method always returns US weeknumbers.

Regards,
Wessel

-----Original Message-----
From: purkka [mailto:pu****@d iscussions.micr osoft.com]
Posted At: Monday, April 11, 2005 1:43 PM
Posted To: microsoft.publi c.dotnet.framew ork.aspnet
Conversation: How to find out a week of the day in C#?
Subject: Re: How to find out a week of the day in C#?

Hoops

Sorry. I did not mentioned, that my ASP.NET application fetch datevalues

(1/2/2005, 11/2/2005...) from Access db. Values are shown as a list in
a
datagrid which should also provide week numbers like this:

Week Date Name .....
-------------------------------
15 12.4.2005 John Smith .....

With rgds
MP

"Wessel Troost" wrote:

Try this:

System.Globaliz ation.CultureIn fo myCI = new CultureInfo("en-US");
myCI.Calendar.G etWeekOfYear( DateTime.Now,
System.Globaliz ation.CalendarW eekRule.FirstFo urDayWeek,
System.DayOfWee k.Sunday );

Greetings,
Wessel

-----Original Message-----
From: purkka [mailto:pu****@d iscussions.micr osoft.com]
Posted At: Monday, April 11, 2005 1:02 PM
Posted To: microsoft.publi c.dotnet.framew ork.aspnet
Conversation: How to find out a week of the day in C#?
Subject: How to find out a week of the day in C#?

Hi

I did not find any solution from Internet how to do it. There is a lot
of
samples how to retrieve day of the week, but not number of the week.

With rgds

MP