Frustrating problem with DateTime, we have a section with a date picker on and if the culture is set to en-GB and the date is 01/11/2012 (dd/mm/yyyy) and then the culture is swapped to Chinese (zh-CN) the date is passed in the old culture format and when it is converted to a DateTime the datetime becomes 2012/1/11 when the culture should be (yyyy/mm/dd).
This seems to be the only culture that I have come across where the conversion is going wrong as it should be 2012/11/1 as 11 is the month.
Does anyone have any ideas why it isn't converting correctly?
Sorry guys this is my fault for not being clear enough, more detail needed.
We have a reporting form that allows users to select a date range, on that form we use use a date range picker (http://www.filamentgroup.com/lab/update_date_range_picker_with_jquery_ui/) to populate a readonly textbox that is submitted to filter the results. Users can select from a dropdown their current culture (needed for our users as they wanted to easily swap between English and Chinese without changing browser settings, If the culture is en-GB then the date range string may read "01/01/2012---01/11/2012" which is 1st January 2012 - 1st November 2012. This is stored in the url, e.g: &DateRange=01%2F01%2F2012+---+01%2F11%2F2012.
Now if the user swaps to Chinese it calls the current page with all the same query parameters but also with the culture parameter changed (we allow the culture to be overridden by an URL parameter) which means the dateformat 01/11/2012 is in the query string, when we pass this using:
DateTime.TryParse(endDateString, out endDate);
the DateTime object contains a date of 11th January 2012 instead of 1st November 2012.
Is there a way I could store the culture info that the date string is in and use that to convert to the new culture info if the culture is swapped?
Any better ideas would be greatly appreciated, swapping from en-GB to en-IN (India) seems to work fine as does swapping to es-MX (Mexico). It just seems to be chinese but that could be pot luck based on these languages date formats.
Many thanks for taking the time to read this.
DateTime.TryParse(endDateString, out endDate);
is using whatever culture is default on the server.
The basic solution would be:
var ci = GetCultureInfoFromRequest();
DateTime.TryParse(endDateString, out endDate, ci);
Use strings to move datetime around in such cases, if you are not processing datetime and just storing it.After that you can change the format before storing it in the database.
Related
Here is a scenario.
You have a string that represents a date i.e. "Jan 25 2016 10:10 AM".
You want to know whether it represents a date in a specific culture.
You want to know what dateTime pattern satisfies this date string.
Example:
Date string is "Jan 25 2016 10:10 AM"
Culture is en-US
The POSSIBLE format for it could be "MMM dd yyyy HH:mm tt"
Implementation:
To get the list of all dateTime patterns you can get a CultureInfo.DateTimeFormat.GetAllDateTimePatterns()
Then try the overloaded version of DateTime.TryParseExact(dateString, pattern, culture, DateTimeStyles.None, out resultingDate) for each of the patterns above and see whether it can parse a date.
That should give you the needed dateTime pattern.
HOWEVER if we iterate all those patterns it will not find any matches!
This is even more weird if you try and use a DateTime.TryParse(dateString, culture, DateTimeStyles.None, out resultingDate) and it DOES parse the correct date!
So the question is how come the DateTime.TryParse knows the pattern of a date string when this info is not a part of CultureInfo and how to get to this info in a culture?
Thanks!
I agree with xanatos, there is no perfect solution for that and you can't assume that every format GetAllDateTimePatterns returns can be perfectly parsable with Parse or TryParse methods.
From DateTimeFormatInfo.GetAllDateTimePatterns;
You can use the custom format strings in the array returned by the
GetAllDateTimePatterns method in formatting operations. However, if
you do, the string representation of a date and time value returned in
that formatting operation cannot always be parsed successfully by the
Parse and TryParse methods. Therefore, you cannot assume that the
custom format strings returned by the GetAllDateTimePatterns method
can be used to round-trip date and time values.
If you see Remarks section on the page, there are only 42 formats that can be parsed by TryParse method in 96 formats that GetAllDateTimePatterns method returns for it-IT culture for example.7
Tarek Mahmoud Sayed responded as;
Parse/TryParse are implemented as finite state machine so it doesn’t
really use the date patterns in parsing. It just split the parsed
string into tokens and try to find if the token match specific part of
the date (like Month, day, day of week…etc.). in the other hand
ParseExact/TryParseExact will just parse the string according to the
passed format pattern.
In short, Parsing is really hard because there are a lot of things that can trip it up. And someone in some government could suddenly decide that country X should use D/M/Y instead of M/D/Y, or could have someone entering data used to the other format.
I talk a little about this on a blog post (toward the bottom-ish) https://web.archive.org/web/20190110065542/https://blogs.msdn.microsoft.com/shawnste/2005/04/05/culture-data-shouldnt-be-considered-stable-except-for-invariant/
DateTime.Parse attempts to guess what the input might be based on the pattern(s) and separators it sees in the specified culture. Unfortunately, some cultures are REALLY hard to guess at. For example, . has been used for time formats in some locales, so is 1.1.1 12.12.12 the 12th day of December 2012? Or the 1st day of January 2001?
ParseExact (as the other answers suggest) is more reliable as you can tell it exactly what you're looking for - even better, you can also tell the user exactly what to enter. (Hopefully this is human input). Unfortunately it requires the user to follow the template.
This is also why most date controls you encounter, especially on the web, have separate fields for month, day & year.
For machine readable formats its best to spit it out in some standard format and read it back in with that exact same format. We've had customers send data from one country to another using the CurrentCulture and wonder why their vendor can't read it ;-)
I have a datetime in this format "Wednesday, December 04, 2013". I want to translate it to different cultures at runtime so that i am able to store that in database according to culture.
This is my code:
dysMngmt.Day = curntDate.ToString("D");
The one line code above is getting the day.
So,please help me.
You can use the second argument of the ToString function, which enables you to pick a culture you see fit:
curntDate.ToString("D", CultureInfo.GetCultureInfo("en-US"))
As a side note, why are you saving the date in your database as a string? Why not use a native date date type? It will take less space and allow you comparisons etc., and then you'd just use the currect culture when reading it out of the database.
Unless you have a very good reason for handling the culture of each date seperatly within the application you should set this at the application level so that the default ToString() works with your intended culture.
http://support.microsoft.com/kb/306162
Also, you should probably also not store dates as text in your database.
UPDATE This looks to be a bug in Windows 7. I tested the same scenario with Windows 8 and I cannot replicate this there. Please see the MS Bug Report that I posted on this issue if you want more information. Thank you again to all that helped.
UPDATE 2 The error happens on Server 2008 R2 as well (Kind of expected that)
Original Submission
Using the examples on the following page Date Formats I am able to control the format of my date. However, one of my clients, using Windows 7, modified their calendar to display their short date like this 'ddd MM/dd/yy', see the image for the settings. .
This displays the clock like this .
This works fine except when I use a date on their machine. When I format the date like the following...
String.Format("{0:MM/dd/yy}", dt); //the result is 06 04 13, notice the spaces
If I take off the ddd to display the day of week in the calendar settings and use the same format option I see the following...
String.Format("{0:MM/dd/yy}", dt); //the result is 06/04/13, this time it has forward slashes
The .ToShortDateString() option on the date gives me "Tue 06/04/13" and crashes when going into a database. This is how the issue was found.
Outside of hard coding the format, i.e. joining the month to the forward slash to the day etc, does anyone know of what else I can try to get this to work?
It sounds like you are formatting the date as a string in order to send it in via some SQL. Have you considered using command parameters for this instead of string formatting?
Using the InvariantCulture should work. I created a test console app to check it. The code changes the thread's current culture to be the Invariant one:
class Program
{
static void Main(string[] args)
{
/// Displays '06 04 13'
Console.WriteLine(string.Format("{0:MM/dd/yy}", System.DateTime.Now));
System.Threading.Thread.CurrentThread.CurrentCulture = System.Globalization.CultureInfo.InvariantCulture;
/// Displays '06/04/13'
Console.WriteLine(string.Format("{0:MM/dd/yy}", System.DateTime.Now));
Console.ReadLine();
}
}
Edited To Note: This looks to be a bug with Windows 7. When changing the short date pattern via the control panel, using the "additional settings" tab as in the OP's post, both the CurrentCulture and CurrentUICulture's date separator gets changed as well.
When you modify the short date format, it looks like the first non-format character is picked up as the date separator for the current culture. Both CurrentCulture and CUrrentUiCulture are modified to reflect that [unintended] customization. Looks like some [bright] developer made the [unwarranted] assumption that nobody would ever have a short date format that included something like day of the week.
Nice catch! Are you going to report the bug to Microsoft?
If you use the invariant culture to format dates, etc., user settings won't affect you. Try something like
String.Format( CultureInfo.InvariantCulture , "{0:MM/dd/yy}", dt);
or use an instance of the culture you want:
CultureInfo usa = CultureInfo.GetCultureINfo("en-US") ;
string.Format( usa , "{0:MM/dd/yy}" , dt ) ;
However, if the culture you specified matches the current culture set for the Windows OS, user customizations are applied: meaning, you'll have the same problem unless you use a culture that isn't the current windows culture.
More details at MDSN:
CultureInfo
Standard DateTime Format Strings
Custom DateTime Format Strings
Without specifying a specific culture, you'll get the current user's CurrentCulture or CurrentUICulture with any user-specified mods applied to it.
For those interested in more information on this please go to the MS Forums post that I put HERE.
when I pass the datetimeoffset.datetime to a SQL server stored procedure, the result get the month and date wrong way around.
E.g when I pass 11/12/2012, the result became 12/11/2012. So 11th of December was changed to twelveth of November.
Is anything I can do to find the problem?
In short: it might be because of culture settings that you need to check in your C# code and SQL Server. In Europe and US the date formatting are quit different.
For example: us default date formatting is "mm/dd/yyyy", while EU is "dd/mm/yyyy"
Here is a post that directly address this culture settings in C# - How can I get date and time formats based on Culture Info?
OK in your stored procedure you must use cast or covert to format it
read this link about cast datetime type and formats
http://msdn.microsoft.com/en-us/library/aa226054%28SQL.80%29.aspx
My C# application have to read some date from MySQL database. Problem I have is that format of date depends on system localisation settings.
My question is if is possible that I always get date in formats yyyy-MM-dd hh:mm:ss, and yyyy-MM-dd, no matter of localisation settings.
Thank you in advance!
If you are storing the dates as true date or datetime values, your application will get the raw binary data back, and it will not be subject to localization until you create a string representation of the date values. My guess is that you are looking at the values in the debugger or using Console.WriteLine(theValue);, which will use the current locale. Always include the desired format and/or the desired culture when converting non-string values to strings.
If you are storing the dates as strings, you will always have to know exactly what format went into the database.
Assuming the dates are stored as date or datetime: just handle the values as they are, and don't convert them to strings until you need to show them to a user:
DateTime theValue = theReader.GetDateTime(fieldOrdinal);
var theValueAsText = theValue.ToString(CultureInfo.InvariantCulture);
var specificTextRepr = theValue.ToString("yyyy-MM-dd HH:mm:ss");
The theValueAsText variable will be a string representation that is not tied to a specific culture. The specificTextRepr will be your specific text representation.
You shouldn't be reading it back as a string from the database - you haven't shown how you're reading the data, but if you use something to populate a DataTable, or LINQ, or IDataReader.GetDateTime then there's no string formatting involved (assuming it's stored properly in the database, which it looks like it is).
A DateTime value doesn't intrinsically have a format, any more than an int is in decimal or hex - it's how you choose to convert it that matters, and you should almost always avoid doing that formatting unless you really need to.
Since you store the dates in date and date/time specific representations, formatting does not play into it at all (as opposed to some highly discouraged storage schemes when date/time is stored as strings, when formatting does matter, but for a wrong reason).
When you query MySQL from your C# code, you will get the correct dates no matter what your locale is. They will be displayed differently based on the locale, but they will represent the proper date regardless of the locale settings.
You can format the date directly in the query by using
date_format(dob,'%d/%m/%Y')
select date_format(dob,'%d/%m/%Y') dob from student where Id=1
Change
CurrentDate = DateTime.Now.ToString("MMM d, yyyy");
CurrentTime = DateTime.Now.ToString("hh:mm tt");
TO
CurrentDate = DateTime.Now.ToString("MMM d, yyyy",CultureInfo.InvariantCulture);
CurrentTime = DateTime.Now.ToString("hh:mm tt", CultureInfo.InvariantCulture);