Basically,I am reading excel file where one of that columns has date format like : dd/MM/yyyy eg: 11/04/2016
When I am using DateTime.TryParse() to parse that string into datetime method TryParse() treated first numbers like month (number 11 in example above). However the same code running on the other computers will take the second number (04 in example above) as the month.
So my question is why there is a difference between them, what actually decide the behavior of TryParse method?
I think the main difference is in IFormatProvider (hard to say if I can't check some settings in target system), but I usually use other method to get proper DateTime object:
DateTime someDate = DateTime.ParseExact(myStringDate, "dd/MM/yyyy", System.Globalization.CultureInfo.InvariantCulture);
It always gives me what I want no matter how client environment is configured.
Hope this helps. :)
From DateTime.TryParse(String, DateTime) documentation:
Because the DateTime.TryParse(String, DateTime) method tries to parse
the string representation of a date and time using the formatting
rules of the current culture, trying to parse a particular string
across different cultures can either fail or return different results.
If a specific date and time format will be parsed across different
locales, use the
DateTime.TryParse(String, IFormatProvider, DateTimeStyles, DateTime)
method or one of the overloads of the TryParseExact method and provide
a format specifier.
That means your computers have different culture settings which is pointed in CurrentCulture property.
Looks like one computer's current culture have dd/MM/yyyy and the other computer's current culture have MM/dd/yyyy as a standard date and time format.
Since you are sure your values are always in dd/MM/yyyy format, I would use DateTime.ParseExact instead of Datetime.TryParse or DateTime.TryParseExact methods like;
var dt = DateTime.ParseExact(yourColumnValue, "dd/MM/yyyy", CultureInfo.InvariantCulture);
Or you can sets all computers current culture to like the first computer but remember, CultureInfo data is not a stable data that might be change in future with a windows update, .NET Framework version or OS version.
Related
I want datetime.now to return the datetime object in UK format. It does so on my local computer but when I upload the code to the server it does it in US format
DateTime doesn't have any format associated with it. Formatting is just for presentation. You can do:
string formattedDate = DateTime.Now.ToString(CultureInfo.CreateSpecificCulture("en-GB"));
Or supply a specific/custom format like:
string formattedDate = DateTime.Now.ToString("dd/MM/yyyy HH:mm:ss",
CultureInfo.InvariantCulture);
I want datetime.now to return the datetime object in UK format.
There's no such concept, any more than an int is a value "in hex" or "in decimal". A DateTime is just a DateTime - you can specify the format when you convert it to a string. It's really important to understand the difference between an inherent value, and what it looks like after it's converted to text - very few types are aware of a custom, modifiable format to use when converting themselves - it's either provided externally (as for DateTime, numbers etc) or simply fixed.
Before you convert start hard-coding a UK format though, I would strongly advise you to consider exactly what you're doing:
Ideally, avoid the conversion in the first place. A lot of the time, string conversions are unnecessary and can be problematic.
Is the text going to be consumed by another machine? Use an ISO-8601 standard format.
Is the text going to be consumed by a person? Use their culture rather than some arbitrary one you decide on.
... Or display it in a dedicated control...
You can use the overload of the ToString method: ToString("dd/MM/yyyy"), or: ToString("yy/MMM/dd"), etc. etc.
Read more about it here: https://msdn.microsoft.com/en-us/library/zdtaw1bw%28v=vs.110%29.aspx
Also sounds to me that you might want to configure your (UI-)Culture in the web.config? Then it will always be in the same format regardless of the culture of your US/Japanese/european server culture..
More about that here: https://msdn.microsoft.com/en-us/library/bz9tc508%28v=vs.140%29.aspx
LogDate = DateTime.UtcNow.AddHours(1);
I am reading data from an API file, which has this format
<DataPoint>
<Amount>38.361</Amount>
<Time>2014-01-02T12:00:00</Time>
</DataPoint>
when I get the time, and print it at my website at visual studio I get 02/01/2014.
However, If I upload it, I get 1/2/2014.
Why the same code produces different results when I use it at my pc, and when I upload it at the server?
And how I can fix that?
ps: I am programming in C# and I am using the object JArray to get the data if this is important
JArray a = JArray.Parse(text);
But it
That's because of the DateTime CULTURE info. British dates are arranged as dd/MM/yyyy and American dates are MM/dd/yyyy You could just use Datetime.ToString("dd/MM/yyyy") to convert it to datetime format you want to display.
Format in which numeric and datetime values are transformed into string depends on OS culture settings, when you don't set them explicitly in code. Looks like that's the case here.
If you need the same date/numeric format everywhere, no matter how user set's the OS preferences, you should provide IFormatProvider instance which will provide the formatting and override OS default one.
The most commonly used is CultureInfo.InvariantCulture:
var dateString = myDate.ToString(CultureInfo.InvariantCulture);
I have developed a winform application that makes use of the format dd-MM-yyyy hh:mm:ss (24 hr system).
When I try the application on another computer, I get an error, because the standard datetime format there is dd/MM/yyyy hh:mm:ss am/pm.
Moreover, the controls in which the datetime is stored, also hold the datetime string in a different format: d/M/yyyy hh:mm:ss am/pm, eg 1/4/2013 12:00:00 A.M. instead of 01/04/2013 12:00:00 A.M.
Can I force the other system to somehow use the same format?
I am a novice here. Thanks for the help.
When displaying a DateTime object, there are two things to keep in mind.
Culture settings: when you don't specify an explicit culture, the culture that's set by the system your application is running on is used.
Format strings: when converting a DateTime object to a string, you can give it a format string as an argument that specifies how your DateTime object should be formatted. Something like: "d" for a short date pattern or "t" to only display the time.
Combining these two will give you full control over how to display your DateTime objects. You should however be careful in forcing a certain culture setting on the user. If your application should support globalization (so multiple users from different cultures can use your app) you shouldn't depend on a specific culture. Instead, you should store all your data culture-insensitive and format it with the users culture when you display it on screen.
Here is an example how to use both the CultureInfo object and a format string:
string myDate = "10-05-2013 08:52:30";
DateTime date = DateTime.Parse(myDate);
Console.WriteLine(date.ToString("d", new CultureInfo("en-US"))); // 5/10/2013
Console.WriteLine(date.ToString("d", new CultureInfo("nl-NL"))); // 10-5-2013
Console.WriteLine(date.ToString("f", new CultureInfo("nl-NL"))); // vrijdag 10 mei 2013 08:52
You should be able to set the culture for the application to the one you need to use.
System.Threading.Thread.CurrentThread.CurrentUICulture = new System.Globalization.CultureInfo("EN");
I would not recommend to force the system to one date and time format. From my point of view the better question would be, why is your application using a specified format? The .NET Framework is designed that you don't have to care about such things.
Anyway, if you will really force the system to display the data in a specified format, change the thread culture:
System.Threading.Thread.CurrentThread.CurrentUICulture = new System.Globalization.CultureInfo("de-DE")
System.Threading.Thread.CurrentThread.CurrentCulture = new System.Globalization.CultureInfo("de-DE")
My website is hosted on multiple servers at different locations
Everywhere the Culture of the data format is different- we use mm/dd/yyyy format every where but incase some server has the culture set to dd/mm/yyyy then our website generates Datetime exception.
You should be specifying what culture you want to use whenever you convert a string to a date.
The culture you should be using depends on what culture the dates are formatted as. For example, if all dates you are parsing are formatted as Slovak:
String s = "24. 10. 2011";
Then you need to parse the string as though it were in Slovak (Slovakia) (sk-SK) culture:
//Bad:
d = DateTime.Parse(s);
//Good:
d = DateTime.Parse(s, CultureInfo.CreateSpecificCulture("sk-SK")); //Slovak (Slovakia)
If your dates are all in Tajik (Tajikistan Cyrillic), then you need to parse it as tg-Cryl-Tj:
String s = "24.10.11"
DateTime d = DateTime.Parse(s, CultureInfo.CreateSpecificCulture("tg-Cryl-Tj"));
Which leads to the question: what date format are you using? You should not be relying on the locale setting of the server, you should be deciding what format you want.
//Bad
String s = d.ToString();
//Good
String s = d.ToString(CultureInfo.CreateSpecificCulture("si-LK")); //Sinhala (Sri Lanka)
//s = "2011-10-24 12:00:00 පෙ.ව."
i suspect that you prefer to do everything in English. But then you have to decide which variant of English:
en-AU (English Austrailia): 24/10/2011
en-IA (English India): 24-10-2011
en-ZA (English South Africa): 2011/10/24
en-US (English United States): 10/24/2011
i suspect you prefer English (India) (en-IA).
But if you really can't decide what culture to use when converting dates to strings and vice-versa, and the dates are never meant to be shown to a user, then you can use the Invariant Culture:
String s = "10/24/2011" //invariant culture formatted date
d = DateTime.Parse(s, CultureInfo.InvariantCulture); //parse invariant culture date
s = d.ToString(CultureInfo.InvariantCulture); //convert to invariant culture string
Never, ever, store dates internally as strings. Not in the database, not in your app.
If you need to move date values between servers, go binary. Or if you really really have to use strings, use ToString(CultureInfo.InvariantCulture) - or simply serialize the Ticks property.
Also, never pass dates as strings to the database using SQL commands that you build using code. Use SqlParameter for that, or even better, rely on some O/R Mapper, such as Entity Framework or Linq to SQL.
If deployed to a server that's not under your control it's vitally important to make sure your code doesn't have hard-coded dependencies on the culture.
You'll most likely want to search your code for DateTime.Parse or similar. We have a set of extension methods on DateTime that we use instead to force the correct culture.
Never rely on the server's default locale. For your case, this means:
Use prepared statements where you pass the date as (unformatted) date object and not as (formatted) string object. You should never use strings to represent dates in your application anyway, as you cannot perform date-specific functions on them (like adding 1 month, getting the last day of the current week, etc.)
Use SQL functions like to_date and to_char everywhere (exact names depend on your DBMS), if you really need to use string objects in your application
I cam trying to convert a datetime to string and back, but making it so that it works for all cultures.
I basically have a Textbox (tbDateTime) and a label (lbDateTime). The label tells the user, in which format the software expects the input of tbDateTime. The input of the Textbox will be used for an MySQL command.
Currently it works like this:
lbDateTime.Text = "DD.MM.YYYY hh:mm:ss"; // I live in germany
DateTime date = Convert.ToDateTime(tbDateTime.Text);
String filter = date.ToString("yyyy-MM-dd HH:mm:ss");
Now my question:
Is it possible to determine the format-string for lbDateTime.Text based on the current culture?
Which format does the Convert.ToDateTime function uses?
I hope you can help me. I have actually no pc here to test different cultures, so I'm very afraid that I make something wrong.
Instead of using the Convert.ToDateTime method you can use the DateTime.Parse or DateTime.ParseExact methods. Both allow you to pass a culture that tells how you expect the date to be formatted.
The DateTime.ParseExact method also allows you to specify the format you expect, so you can parse more or less any format with this method.
Edit:
Regarding Convert.ToDateTime. The documentation says that the current culture is used when parsing: http://msdn.microsoft.com/en-us/library/xhz1w05e.aspx
The current culture can be found using the System.Threading.Thread.CurrentThread.CurrentCulture property.
Edit2:
Oh. You may also want to use DateTime.TryParse and DateTime.TryParseExact if you are unsure whether the given format is invalid.
Edit3:
Lots of edits here... I see that you want to determine the culture string that matches the date the user has entered. There is no general solution that is guaranteed to work here. Say for instance that the user has entered the date 01.02.11. There is no way to be certain if this date is in day.month.year or month.day.year or year.month.day and so on.
The best you can do is to have a list of expected input cultures and start with the most likely and try to parse the date using that. If that fails, you can try the second most likely and so on...
But this is really not recommended. Either give the user an expected format, or better, use a date input box that ensures that you receive the selected date in an appropriate format.
The Convert.ToDateTime method will call DateTime.Parse to parse the string, using the current culture (CultureInfo.Current).
You can specify a culture when parsing the string. Example:
DateTime data = DateTime.Parse(tbDateTime.Text, new CultureInfo("en-GB"));
You can use DateTime.ParseExact (or DateTime.TryParseExact) to parse the string using a custom date format. Example:
DateTime data = DateTime.ParseExact(tbDateTime.Text, "dd'.'MM'.'yyyy HH':'mm':'ss", CultureInfo.InvariantCulture);
Another solution :
// Specify the current language (used in the current system you are working on)
CultureInfo currentCulture = CultureInfo.GetCultureInfo(CultureInfo.CurrentCulture.ToString());
// Specify the language that we need
CultureInfo myLanguage = CultureInfo.GetCultureInfo("en-US");
// Adapt the DateTime here, we will use the current time for this example
DateTime currentDate = DateTime.Now;
// The date in the format that we need
string myDate = DateTime.Parse(currentDate.ToString(), currentCulture).ToString(myLanguage);