How to check for current culture in my ado.net code?

Question

I am trying to parse a date that is coming from a source as "02/11/2013"

In my application, I set the user's culture to either en-CA or en-FR, with their date format's being "dd/MM/yyyy" or "M/d/yyyy"

If I parse the date, and pass in the format, will this work or does it depend on which format I saved to the database?

 if (DateTime.TryParseExact(dateString, Thread.CurrentThread.CurrentCulture.DateTimeFormat.ShortDatePattern, null, System.Globalization.DateTimeStyles.None, out dtResult))
{
    dt = dtResult;
}

I can think properly right now so I need some clarification.

Me passing in the format of "dd/MM/yyyy" or "M/d/yyyy", does this format the date no matter what format the source is in, or is it me telling the datetime parse that the source will be in this format so use this?

What I am weary of is that someone is saving to the db in one format, and then a french person wants to read the date and their own format (yes I should be storing in utc).

score 2 · Answer 1 · answered Feb 14 '13 at 07:21

ADO.NET is strongly typed; there are well known types for storing most data. In the case of dates, that would be DateTime in .NET and datetime in most database systems. If you ever need to worry about culture, then you're already doing it wrong, because you are passing the data around as a string rather than as a DateTime / datetime.

This then renders your concern here redundant:

What I am weary of is that someone is saving to the db in one format, and then a french person wants to read the date and their own format (yes I should be storing in utc).

because a DateTime / datetime has no notion of format - it is simply a date/time value. Any UI presentation / parsing of string data should be completely isolated and specific to the UI. Beyond the UI code you should (when talking about dates/times) be using DateTime / datetime exclusively.

Similarly, when storing an integer you should be using int.

score 0 · Answer 2 · edited May 23 '17 at 10:24

If the date is stored only as "02/11/2013" without any other culture identifying information there is no way for you to know how to properly interpret it! You are absolutely right being worried that somebody with a en-FR culture might save a date to the database as "02/11/2013" meaning the 2nd of November and then somebody with an en-US culture might read that date and interpret it as the 11th of February.

You should only pass the current culture if you know that is relevant, meaning that you know the date string was generated using that culture.

A better approach is to NOT store dates like that in the first place. It's best to store the date in a format that includes timezone as well as format information such as the Internet Date/Time RFC 3339 format.

Or, if you can't, at least make sure to take the date and always convert it to say en-US culture before storing in the database and than pass that culture to the DateTime.Parse when reading from the database.

The .NET XML serialization code for dates can come in handy when serializing/deserializing dates in RFC 3339 format. See this SO post for more info..

How to check for current culture in my ado.net code?

2 Answers2