I currently have an application that needs to support multiple cultures. A date string is being passed in and is being parsed to a DateTime object. To allow for multiple cultures I am first setting the thread's culture and UICulture.
Here is an example of my code as it is:
First I set the culture for this thread. This is passed in on the URL (ex. en-us, en-ca, fr-ca):
CultureInfo ci = new CultureInfo(culture, false);
Thread.CurrentThread.CurrentUICulture = ci;
Thread.CurrentThread.CurrentCulture = ci;
I then take a date string that is also passed in on the URL and convert it to a DateTime. Depending on the culture the date will be passed in as mm/dd/yyyy or dd/mm/yyyy.
I parse the date strings with the following code:
DateTime DateTimeObject;
bool validDate = DateTime.TryParse(DateStringFromURL, Thread.CurrentThread.CurrentCulture, DateTimeStyles.None, out DateTimeObject);
The TryParse works for most cultures and out comes a valid datetime object. A problem arises with en-ca and fr-ca though. If the wrong format is passed in, the datestring does not parse correctly.
The following shows which format .NET seems to expect for each culture:
dd/MM/yyyy MM/dd/yyyy
EN-CA Valid Invalid
FR-CA Invalid Valid
EDIT:
To be more exact here are the examples causing me problems:
For EN-CA:
DateTime.Parse("26/08/2014") //VALID
DateTime.Parse("08/26/2014") //EXCEPTION THROWN
For FR-CA:
DateTime.Parse("26/08/2014") //EXCEPTION THROWN
DateTime.Parse("08/26/2014") //VALID
This is backwards from how other systems treat this culture's date formatting.
Why are the formats seemingly backwards?
Is this a bug with .NET 4.5?
Any and all help would be appreciated, thanks.
NOTE: .NET Version 4.5
You should probably look into Invariant culture. That is what you should use for your URL passing. You can use the local culture for display purposes on the client.
Typically, whenever you are storing data (for example, in a database or file ) it is best to use the Invariant culture. When displaying data you can use the local culture. When passing data around, you want to use Invariant culture.
Read more here.
I believe your assumptions are wrong. This console application:
static void Main(string[] args)
{
var enca = new CultureInfo("en-ca", false);
var frca = new CultureInfo("fr-ca", false);
Console.WriteLine("enca dd/MM/yyyy: " + ParseDate("26/08/2014", enca));
Console.WriteLine("enca MM/dd/yyyy: " + ParseDate("08/26/2014", enca));
Console.WriteLine("frca dd/MM/yyyy: " + ParseDate("26/08/2014", frca));
Console.WriteLine("frca MM/dd/yyyy: " + ParseDate("08/26/2014", frca));
Console.ReadKey();
}
static bool ParseDate(string date, CultureInfo culture)
{
try
{
DateTime.Parse(date, culture);
return true;
}
catch
{
return false;
}
}
Has output:
enca dd/MM/yyyy: False
enca MM/dd/yyyy: True
frca dd/MM/yyyy: False
frca MM/dd/yyyy: True
There is definitely a bug in data parsing for Canadian culture. If you try following having CurrentCulture = "en-CA":
DateTime.ParseExact("2014/09/20", "yyyy/MM/dd", Thread.CurrentThread.CurrentCulture)
you'll get following exception:
A first chance exception of type 'System.FormatException' occurred in mscorlib.dll
works fine if you replace / with something else, like - or with InvariantCulture.
Related
if (!IsPostBack && !Page.IsCallback)
{
double OffsetHrs = GetTimeZoneOffsetFromCookie();
string dateFormat = ServiceManager.LocalizationService.GetString("AppHeaderTop", "DateFormat", "g");
CultureSelected CultureSelected = GetCultureSelected();
ASPxLabelCurrentTime.Text = DateTime.Now.ToUniversalTime().AddHours(-OffsetHrs).ToString(dateFormat);
if (CultureSelected.CultureCode != "en-US")
{
DateTimeFormatInfo usDtfi = new CultureInfo("en-US", false).DateTimeFormat;
DateTimeFormatInfo currentDtfi = new CultureInfo(CultureSelected.CultureCode, false).DateTimeFormat;
ASPxLabelCurrentTime.Text = Convert.ToDateTime(ASPxLabelCurrentTime.Text, usDtfi).ToString(currentDtfi.ShortDatePattern); //what can i Use here ?
}
Let say Output of ASPxLabelCurrentTime.Text
for en-US culture is 11/2/2015 4:14 PM (70)
If I select specific culture I want this datetime 11/2/2015 4:14 PM (70) to appear in that specific culture format.
Your question seems unclear but I try to give a shot.
First of all, what is this (70) exactly? Where is this came from? en-US culture can't parse this string without using it in a string literal delimiter with ParseExact or TryParseExact methods. On the other hand, since you assing ASPxLabelCurrentTime.Text the result of the DateTime.Now.ToUniversalTime().AddHours(-OffsetHrs).ToString(dateFormat) code, I don't believe this (70) part is really an issue on this question.
Second, If I understand clearly, the problem seems the usage of DateTime.ToString(string) method.
ASPxLabelCurrentTime.Text = Convert.ToDateTime(ASPxLabelCurrentTime.Text, usDtfi)
.ToString(currentDtfi.ShortDatePattern);
// ^^^ Problem seems here
Okey let's say you successfully parse this ASPxLabelCurrentTime.Text with usDtfi culture (which is en-US), but with this .ToString(string) method, you are not using currentDtfi settings actually, you are using CurrentCulture settings when you generate formatted string representation of your DateTime.
From DateTime.ToString(String) doc;
Converts the value of the current DateTime object to its equivalent
string representation using the specified format and the formatting
conventions of the current culture.
Since we don't know what GetCultureSelected method returns exactly, it may or may not be the same culture with currentDtfi.
I strongly suspect, you can solve this problem to using that culture as a second parameter in ToString method as;
ASPxLabelCurrentTime.Text = Convert.ToDateTime(ASPxLabelCurrentTime.Text, usDtfi)
.ToString(currentDtfi.ShortDatePattern, currentDtfi);
IF this (70) is really part of on your string, you need to ParseExact or TryParseExact methods to supply exact format of it.
string s = "11/2/2015 4:14 PM (70)";
DateTime dt;
if(DateTime.TryParseExact(s, "MM/d/yyyy h:mm tt '(70)'", CultureInfo.GetCultureInfo("en-US"),
DateTimeStyles.None, out dt))
{
ASPxLabelCurrentTime.Text = dt.ToString(currentDtfi.ShortDatePattern, currentDtfi);
}
Scope:
I have been trying to develop a super-tolerant DateTime.Parse routine, so I decided to give most "widely-used" formats a try to better understand the format masks.
Problem:
I have defined a specific format (String) which I use as myDate.ToString(format), and it works wonders. The problem is, If I get this same String (result of the .ToString(format) operation), and feed it back to DateTime.TryParseExact (...) it fails.
Code / Test:
System.Globalization.CultureInfo provider = System.Globalization.CultureInfo.InvariantCulture;
// Defining Format and Testing it via "DateTime.ToString(format)"
string format = "MM/dd/yyyy HH:mm:ss tt";
string dtNow = DateTime.Now.ToString (format);
Console.WriteLine (dtNow);
// Trying to Parse DateTime on the same Format defined Above
DateTime time;
if (DateTime.TryParseExact (dtNow, format, provider, System.Globalization.DateTimeStyles.None, out time))
{
// If TryParseExact Worked
Console.WriteLine ("Result: " + time.ToString ());
}
else
{
// If TryParseExact Failed
Console.WriteLine ("Failed to Parse Date");
}
Output is : "Failed to Parse Date".
Question:
Why can I use the format string to format a certain date as text, but I can't use the same format to feed the string back to a date object ?
EDIT:
I have added part of my method to this example, and I would like to know why the "ParseDate" method fails to return a proper date, given that the "String" is in the right format.
Since you use DateTime.ToString() method without any IFormatProvider, this method will use your CurrentCulture settings.
That's why your
string dtNow = DateTime.Now.ToString (format);
line might generate a different string representation than MM/dd/yyyy HH:mm:ss tt format.
Three things can cause this issue;
Your CurrentCulture has a different DateSeparator than /
Your CurrentCulture has a different TimeSeparator than :
Your CurrentCulture has a different or empty string as a AMDesignator and/or PMDesignator
Since you try to parse your string with provider (which is InvariantCulture) on your DateTime.TryParseExact method, generate your string based on that provider as well.
string dtNow = DateTime.Now.ToString(format, provider);
You told your CurrentCulture is pt-BR and this culture has empty string "" as a AMDesignator and PMDesignator. That's why your dtNow string will not have any AM or PM designator on it's representation part.
Here a demonstration.
I accept date info from the user, via date picker. I need to store them in a culture neutral way. The problem I am facing is, if I store the date as per en-US format (based on calendar settings), namely 11/20/1990 it will fail to parse when the culture is en-GB.
And vice versa happens when culture is en-US, date stored as per UK format, dd/mm/yyyy refuses to parse. How do I store date info in a culture neutral way in a file so that, I get the date to work in both locations?
DateTime.TryParse(userEnteredValue, out result);
result.ToShortDateString(); //this is what I am doing
tried this code for invariant culture
string input = "20/10/1983";
DateTime userInput;
bool result = DateTime.TryParse(input, out userInput);
string invariantCulture = userInput.Date.ToString(CultureInfo.InvariantCulture);
DateTime storedValue;
result = DateTime.TryParse(invariantCulture, out storedValue);
tried this code with en-GB calendar settings, second statement DateTime.TryParse fails infact.
#Soner Gönül's answer is spot on if you are saving the dates to a database. However, you mention that you are looking to round-trip a DateTime to and from a file.
As the file is presumably a text file you'll need to write the DateTime in a culture neutral manner. You can do this by using the "O" format specified on the DateTime.ToString method. This will output a string representation that complies with ISO 8601. The resultant string can be parsed using DateTime.Parse without the need for culture information.
As an example:
string filename = #"c:\temp\test.txt";
string usDateString = "11/18/2014 12:32"; // MM/dd/yyyy
string ukDateString = "18/11/2014 12:33"; // dd/MM/yyyy
//I'm mimicking you getting the DateTime from the user here
//I'm assuming when you receive the date(s) from the front
//end you'll know the culture - if not then all bets are off.
DateTime usDate =
DateTime.Parse(usDateString, CultureInfo.GetCultureInfo("en-US"));
DateTime ukDate =
DateTime.Parse(ukDateString, CultureInfo.GetCultureInfo("en-GB"));
//write the dates to a file using the "o" specifier
File.AppendAllText(filename, usDate.ToString("o") + Environment.NewLine);
File.AppendAllText(filename, ukDate.ToString("o") + Environment.NewLine);
//read them back in as strings
string[] contents = File.ReadAllLines(filename);
foreach (var date in contents)
{
//prove we can parse them as dates.
Console.WriteLine(DateTime.Parse(date).ToString());
}
This creates a file with the contents:
2014-11-18T12:32:00.0000000
2014-11-18T12:33:00.0000000
and on my system (in the UK) it prints:
18/11/2014 12:32:00
18/11/2014 12:33:00
if I store the date as per en-US format...
Please stop! Looks like you try to save your DateTime values with their string representations.
A DateTime doesn't have any implicit format. It has just date and time values. String representations of them can have a format. Generate your insert queries and pass your DateTime values directly with parameterized way.
Please read;
Bad habits to kick : choosing the wrong data type
If you want to get string representations of your DateTime values with specific format, you can always use DateTime.ToString() method and it's overloads.
Your en-GB culture can parse MM.dd.yyyy (since you use / format specifier which replaces itself supplied culture DateSeparator) and en-US culture can parse MM/dd/yyyy as well.
But since you use .ToShortDateString() method, this represents your datetime based your CurrentCulture settings. As a solution, you can set this property which culture you want and ToShortDateString works based on it.
result = DateTime.TryParse(invariantCulture, out storedValue);
tried this code with en-UK calendar settings, second statement
DateTime.TryParse fails infact.
Because this DateTime.TryParse uses your CurrentCulture and since your invariantCulture variable is 10/20/1983 00:00:00, that means this is not a standard date and time format for your CurrentCulture.
There is no such a culture as en-UK by the way.
10/20/1983 00:00:00 is MM/dd/yyyy HH:mm:ss format. But en-GB culture doesn't have this format as a standard date and time format, that's why your method returns false.
As an alternative, you can use custom format strings like;
string s = "10/20/1983 00:00:00";
string format = "MM/dd/yyyy HH:mm:ss";
DateTime dt;
if (DateTime.TryParseExact(s, format, CultureInfo.GetCultureInfo("en-GB"),
DateTimeStyles.None, out dt))
{
Console.WriteLine(dt);
}
I bumped into this question and figured I'd bring in some other way nobody has mentioned yet:
DateTime.ToBinary() for serializing and DateTime.FromBinary(Int64) for deserialization.
What these do is the following:
ToBinary() returns a long which can be easily stored in a culture invariant way.
FromBinary(Int64) will return a DateTime object from the long parameter supplied.
(They even take the date time Kind property into consideration).
And here's some code to go with it:
DateTime d1l = DateTime.Now;
long dl = d1l.ToBinary();
DateTime d2l = DateTime.FromBinary(dl);
DateTime d1u = DateTime.UtcNow;
long du = d1u.ToBinary();
DateTime d2u = DateTime.FromBinary(du);
Console.WriteLine("Local test passed: " + (d1l == d2l).ToString());
Console.WriteLine("d2l kind: " + d2l.Kind.ToString());
Console.WriteLine("Utc test passed: " + (d1u == d2u).ToString());
Console.WriteLine("d2u kind: " + d2u.Kind.ToString());
And the console output:
Local test passed: True
d2l kind: Local
Utc test passed: True
d2u kind: Utc
I find this to be pretty neat!
String s = "24. 11. 2001";
d = DateTime.Parse(s, CultureInfo.CreateSpecificCulture("sk-SK"));
en-AU (English Austrailia): 24/11/2001
en-IA (English India): 24-11-2001
en-ZA (English South Africa): 2001/11/24
en-US (English United States): 11/24/2001
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 = "11/24/2001" //invariant culture formatted date
d = DateTime.Parse(s, CultureInfo.InvariantCulture); //parse invariant culture date
s = d.ToString(CultureInfo.InvariantCulture); //convert to invariant culture string
I tried to figure out a solution via this approach, please let me know if its correct.
The code which I use is below.
For Saving date time I use ticks as below.
DateTime userInput;
bool result = DateTime.TryParse(this.dpSave.Text, out userInput);
if (result)
{
long ticks = userInput.Ticks;
System.IO.File.WriteAllText(#"D:\folder\Ticks.txt", ticks.ToString());
}
else
{
MessageBox.Show("Date time parse failed");
}
For loading it back, I use
if (System.IO.File.Exists(#"D:\folder\Ticks.txt"))
{
string contents = System.IO.File.ReadAllText(#"D:\Sandeep\Ticks.txt");
long ticks;
if (long.TryParse(contents, out ticks))
{
DateTime storedDateTime = new DateTime(ticks);
MessageBox.Show("Stored Date" + storedDateTime.ToShortDateString());
}
else
{
MessageBox.Show("Unable to obtain stored dates");
}
}
this seems to work, provided, I save using en-US culture and load using en-GB culture.
please let me know if this is the right approach!
a) Exchange data shall always be stored culture invariant (xml etc)
b)You've gotta to be careful with the terminology.
What you exactly mean is culture INVARIANT (and not 'culture neutral').
There are three types of cultures:
1) invariant
2) culture neutral (e.g. "en")
3) culture specific (e.g "en-US")
public DateTime getdate3()
{
CultureInfo Invc = CultureInfo.InvariantCulture; //culture
string cul = Thread.CurrentThread.CurrentCulture.Name;
CultureInfo us = new CultureInfo(cul);
string shortUsDateFormatString = us.DateTimeFormat.ShortDatePattern;//pattern
DateTime dt = Convert.ToDateTime(DateTime.Now);
TimeZoneInfo myZone = TimeZoneInfo.FindSystemTimeZoneById("India Standard Time"); //india zone
DateTime dateindia = TimeZoneInfo.ConvertTime(dt, myZone);
string dt1 = Convert.ToDateTime(dateindia).ToString(shortUsDateFormatString); //string format
}
Why is Convert.ToDateTime behaving strangely for the following values?
The following works just fine:
var value = "08/01/2011";
var dateTime = Convert.ToDateTime(value);
The result is: {08/01/2011 00:00:00} --- which is just expected.
But now, when I do this:
var value = "07/21/2011";
var dateTime = Convert.ToDateTime(value);
I get an exception:
'Convert.ToDateTime("07/21/2011")' threw an exception of type 'System.FormatException'
"07/21/2011";
This is not a valid date, since 21 will be interpreted as the month.
Try explicitly specifying the format instead:
DateTime myDate = DateTime.ParseExact("07/21/2011", "MM/dd/yyyy",
CultureInfo.InvariantCulture);
Edit:
Agreed with #dtb's comment - I just couldn't find a culture where the date you specified is legal. But the general form is:
DateTime myDate = Convert.ToDateTime("07/21/2011", new CultureInfo("XXX"))
where XXX is the name of the culture you want to use (i.e. "en-GB" - which won't work with this format though)
Date/time strings are parsed according to the culture settings for the current thread (which is determined by the regional settings made in the Windows Control Panel).
For example, if the current culture is fr-FR or en-GB, then the input is expected in day/month/year format. If the current culture is en-US, the input is expected in month/day/year format.
You can find the culture settings for the current thread by looking at the Thread.CultureInfo property of Thread.CurrentThread.
If you don't want to parse a date/time string according to the culture settings for the current thread, you have to specify the culture settings explicitly.
Your input seems to be in en-US format, while your system seems to be configured as fr-FR or en-GB. So explicitly specify en-US as culture:
DateTime result = DateTime.Parse("07/21/2011", new CultureInfo("en-US"));
// result.Day == 21
// result.Month == 7
// result.Year == 2011
The reason why your first example works, is because 1 is a valid month, unlike 21.
DateTime result = DateTime.Parse("08/01/2011", new CultureInfo("fr-FR"));
// result.Day == 8
// result.Month == 1
// result.Year == 2011
I am trying to convert my string formatted value to date type with format dd/MM/yyyy.
this.Text="22/11/2009";
DateTime date = DateTime.Parse(this.Text);
What is the problem ?
It has a second override which asks for IFormatProvider. What is this? Do I need to pass this also? If Yes how to use it for this case?
Edit
What are the differences between Parse and ParseExact?
Edit 2
Both answers of Slaks and Sam are working for me, currently user is giving the input but this will be assured by me that they are valid by using maskTextbox.
Which answer is better considering all aspects like type saftey, performance or something you feel like
Use DateTime.ParseExact.
this.Text="22/11/2009";
DateTime date = DateTime.ParseExact(this.Text, "dd/MM/yyyy", null);
You need to call ParseExact, which parses a date that exactly matches a format that you supply.
For example:
DateTime date = DateTime.ParseExact(this.Text, "dd/MM/yyyy", CultureInfo.InvariantCulture);
The IFormatProvider parameter specifies the culture to use to parse the date.
Unless your string comes from the user, you should pass CultureInfo.InvariantCulture.
If the string does come from the user, you should pass CultureInfo.CurrentCulture, which will use the settings that the user specified in Regional Options in Control Panel.
Parsing a string representation of a DateTime is a tricky thing because different cultures have different date formats. .Net is aware of these date formats and pulls them from your current culture (System.Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat) when you call DateTime.Parse(this.Text);
For example, the string "22/11/2009" does not match the ShortDatePattern for the United States (en-US) but it does match for France (fr-FR).
Now, you can either call DateTime.ParseExact and pass in the exact format string that you're expecting, or you can pass in an appropriate culture to DateTime.Parse to parse the date.
For example, this will parse your date correctly:
DateTime.Parse( "22/11/2009", CultureInfo.CreateSpecificCulture("fr-FR") );
Of course, you shouldn't just randomly pick France, but something appropriate to your needs.
What you need to figure out is what System.Threading.Thread.CurrentThread.CurrentCulture is set to, and if/why it differs from what you expect.
Although the above solutions are effective, you can also modify the webconfig file with the following...
<configuration>
<system.web>
<globalization culture="en-GB"/>
</system.web>
</configuration>
Ref : Datetime format different on local machine compared to production machine
You might need to specify the culture for that specific date format as in:
Thread.CurrentThread.CurrentCulture = new CultureInfo("en-GB"); //dd/MM/yyyy
this.Text="22/11/2009";
DateTime date = DateTime.Parse(this.Text);
For more details go here:
http://msdn.microsoft.com/en-us/library/5hh873ya.aspx
Based on this reference, the next approach worked for me:
// e.g. format = "dd/MM/yyyy", dateString = "10/07/2017"
var formatInfo = new DateTimeFormatInfo()
{
ShortDatePattern = format
};
date = Convert.ToDateTime(dateString, formatInfo);
After spending lot of time I have solved the problem
string strDate = PreocessDate(data);
string[] dateString = strDate.Split('/');
DateTime enter_date = Convert.ToDateTime(dateString[1]+"/"+dateString[0]+"/"+dateString[2]);
private DateTime ConvertToDateTime(string strDateTime)
{
DateTime dtFinaldate; string sDateTime;
try { dtFinaldate = Convert.ToDateTime(strDateTime); }
catch (Exception e)
{
string[] sDate = strDateTime.Split('/');
sDateTime = sDate[1] + '/' + sDate[0] + '/' + sDate[2];
dtFinaldate = Convert.ToDateTime(sDateTime);
}
return dtFinaldate;
}
use this to convert string to datetime:
Datetime DT = DateTime.ParseExact(STRDATE,"dd/MM/yyyy",System.Globalization.CultureInfo.CurrentUICulture.DateTimeFormat)
Just like someone above said you can send it as a string parameter but it must have this format: '20130121' for example and you can convert it to that format taking it directly from the control. So you'll get it for example from a textbox like:
date = datetextbox.text; // date is going to be something like: "2013-01-21 12:00:00am"
to convert it to: '20130121' you use:
date = date.Substring(6, 4) + date.Substring(3, 2) + date.Substring(0, 2);
so that SQL can convert it and put it into your database.
Worked for me below code:
DateTime date = DateTime.Parse(this.Text, CultureInfo.CreateSpecificCulture("fr-FR"));
Namespace
using System.Globalization;
You can use also
this.Text = "22112009";
DateTime newDateTime = new DateTime(Convert.ToInt32(this.Text.Substring(4, 4)), // Year
Convert.ToInt32(this.Text.Substring(2,2)), // Month
Convert.ToInt32(this.Text.Substring(0,2)));// Day
Also I noticed sometimes if your string has empty space in front or end or any other junk char attached in DateTime value then also we get this error message