Making my DateTime object think its American :-)

  • Thread starter Thread starter Simon Harvey
  • Start date Start date
S

Simon Harvey

Hi all,

I'm having a bit of a problem working with dates. My computer is british,
but I'm developing an american application so I therefore need to use american
dates. But I can't get my DateTime object to "act" american.

Let me give an example:

In order to take in an american date, I tell it which culture the date will
be formatted according to:

if(!(DateTime.TryParse(txtAvailableFrom.Text, new CultureInfo("en-US"), DateTimeStyles.None,
out arrivalDate))){

This all works fine and the DateTime interprets the textbox contents correctly
as an American date. The problem comes later when I try and use the date.

For example, when I try and do date.ToString(), it outputs it in the British
format. Now this one isnt a problem because I know how to force it to output
the american format. (Though it is inconvienient - I'd like the DateTime
object to remember or know somehow that its got an American date and output
accordingly)

The real showstopper for me though is when it comes to passing the date to
the database.

I want all the dates passed to the database to be in the American format.
Unfortunately, when I pass the DateTime object as a parameter to my Stored
Procedure the date is getting stored in the british format.

It's like the DateTime intrinsically knows that its in Britain, even though
I forced it to accept an American date.

Can anyone tell me if there's anyway I can force it to act like an American
date both when outputing and more importantly when I pass it to the database?
I need it to forget that its in Britain and get it to start acting American
stylee pronto! :-)

Thanks to anyone who can help. This thing has been driving me crazy for ages.
It's getting to crunch time soon and I'm begining to get worried :-(

Thanks again

Simon
 
First, if you're passing it into a database DateTime field, you're not actually
passing it in British format, your table view is likely just outputting that
datetime in your current culture.

Now you say you're developing an American application. Will it run on an
American machine or a British machine? By default, or when you pass CultureInfo.CurrentCulture,
it will use the culture of that machine. So if you use CurrentCulture, it
will use British on your machine and if you ship it to the US, it will use
US formats there. This is ideally how a culture-aware application should
act.

To have the current thread default to a specific culture, use the Application.CurrentCulture
property.

Ideally, what you should be doing is on ALL ToString and parse calls, pass
CultureInfo.CurrentCulture where the information is displayed or taken from
the user. Pass CultureInfo.InvariantCulture when you are storing the information
(database, file, etc). This ensures your application will always display
in the correct culture for the user, and your data will be portable accross
cultures. It's a very small bit of extra typing, but very important when
writing applications that will be used in a different culture.

Just remember when mixing cultures, be careful of how your data is persisted.
 
[aspnet ng trimmed]

Simon said:
Hi all,

I'm having a bit of a problem working with dates. My computer is british,
but I'm developing an american application so I therefore need to use american
dates. But I can't get my DateTime object to "act" american.
Click to expand...

The DateTime structure itself just stores a date and a time; it doesn't
know anything about formats. It's just a number, really.
Let me give an example:

In order to take in an american date, I tell it which culture the date will
be formatted according to:

if(!(DateTime.TryParse(txtAvailableFrom.Text, new CultureInfo("en-US"), DateTimeStyles.None,
out arrivalDate))){

This all works fine and the DateTime interprets the textbox contents correctly
as an American date.
Click to expand...

whispers: DateTimePicker? :)
The problem comes later when I try and use the date.

For example, when I try and do date.ToString(), it outputs it in the British
format. Now this one isnt a problem because I know how to force it to output
the american format. (Though it is inconvienient - I'd like the DateTime
object to remember or know somehow that its got an American date and output
accordingly)
Click to expand...

See above. As expected, in the absence of any explicit cultural
information, the local culture is used - which as you have told us is
British. You wouldn't expect "2,3", entered in an app and parsed into a
double (2.3) with fr-FR, to 'remember' that it's "2,3" not "2.3", would
you? It's just a number.
The real showstopper for me though is when it comes to passing the date to
the database.

I want all the dates passed to the database to be in the American format.
Unfortunately, when I pass the DateTime object as a parameter to my Stored
Procedure the date is getting stored in the british format.
Click to expand...

Now this is confusing. If you have a SQL Server stored proc with a date
type parameter, and you use a SqlParameter object to supply the value
of this parameter, there shouldn't be a problem. The only way I can
think of that you might get a problem is if the date is being converted
to a string, supplied to a text parameter (eg a varchar) and converted
back within the sproc. Is this happening? Let's see the code that
invokes the sproc, along with the parameter-filling stuff.
 
Stupid suggestion, but wouldn't it be easier, for the duration of the
development, to go through Control Panel and change your regional settings
to English(United States).

Steve
 
Try this stuff in a web.config file...

<!--2/10/2006 10:52:49 AM -->
<globalization culture="auto" uiCulture="auto" /> // on my "American"
machine

<!--2/10/2006 10:52:49 AM-->
<globalization culture="en-US" uiCulture="en-US" />

<!--10/02/2006 10:55:56-->
<globalization culture="en-GB" uiCulture="en-GB" />

<%= Clinton Gallagher
NET csgallagher AT metromilwaukee.com
URL http://clintongallagher.metromilwaukee.com/
 
I'm with Steve on this one. Change your PC setting in control panel for
the duration of your build. That would only apply if the host machine
is going to be in the US. Ive read about people have problems changing
CultureInfo.

Jeremy
http://blackstaronline.net/hgtit
 
I've had this problem before, too. I vaguely recall solving it by
passing the date to SQL server as a string representing a universal
date object, e.g.

sqlParam.Value = String.Format("{0:yyyy-MM-dd}", DateTime.Now);

It was a long time ago, so it may need some tweaking, but hopefully
this gives you something to start with.
 
A fantastic link - thank you. That has put a smile on my day ;-p

One that *really* grated on me: the Steam (Valve) installer asks you to
select a language, and lists e.g. French with the French flag, German with
the German flag, and (at the top) English with the stars and stripes. Much
gnashing of teeth over here in the UK.

<g>

Marc
 
Hehe. Obviously, they have got the flags backwards. We Yanks are all simply
transplanted British Subjects, as we so often forget.
 
Try this

System.Threading.Thread.CurrentThread.CurrentCulture = new
System.Globalization.CultureInfo("en-US");

or ....

System.Threading.Thread.CurrentThread.CurrentCulture = new
System.Globalization.CultureInfo("en-GB");

This will set the date time control to work in American/British
formating without screwing with your control panel settings
 
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