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Formatting Date with abbreviated month, while adhering to culture date structure

Developing a multilanguage application, and trying to format a DateTime object to string within a limited space in a table. Full month names might be too long, so we have to use abbreviations.
Some cultures have the format "Oct 12", some have "12. okt" and so on.
The standard .ToString("m") is almost what I want, but with abbreviations:
https://learn.microsoft.com/en-us/dotnet/standard/base-types/standard-date-and-time-format-strings#MonthDay
Similar question, but the answer won't work for us, as this dictates the order of month and day:
Formatting Date String abbreviating month
Is there any way of getting the overall structure of a culture's date formatting, like order of day and month, with or without "." after the number etc? Or another way of generating the required string? This feels like it should be fairly straight forward, as all the pieces are already present.

As per the documentation you linked, the custom date and time format "m" is defined by a CultureInfo's DateTimeFormat.MonthDayPattern property. So I'd look that up for the current culture and customize the format string. Then use the modified format string with ToString.

I was able to solve this myself using the culture's DateTimeFormat wich provides a MonthDayPattern. By simply replacing "MMMM" with "MMM" this will solve the challenge, at least for the locales that we plan to support. I have not tested with all possible locales.
(I know it won't work for "ja-JP", wich has special characters in their pattern)
DateTime date = DateTime.Now;
CultureInfo culture = new("en-US", false);
DateTimeFormatInfo dateTimeFormat = culture.DateTimeFormat;
string pattern = dateTimeFormat.MonthDayPattern.Replace("MMMM", "MMM");
string formatted = date.ToString(pattern, culture);
The pattern for "en-US" goes from "MMMM d" to "MMM d" giving "Oct 13"
The pattern for "nb-NO" goes from "d. MMMM" to "d. MMM" giving "13. okt."

How does DateTime.TryParse know the date format?

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 ;-)

Transform between datetime formats

I am facing a problem in which I need to transform dates in a given input format into a target one. Is there any standard way to do this in C#?
As an example say we have yyyy.MM.dd as the source format and the target format is MM/dd/yyy (current culture).
The problem arises since I am using a parsing strategy that gives priority to the current culture and then if it fails it tries to parse from a list of known formats. Now say we have two equivalent dates one in the source culture above (2015.12.9) and the other in the current culture (9/12/2015). Then if we attempt to parse this two dates the month will be 12 for the first case and in the second will be 9, so we have an inconsistency (they were supposed to mean be the same exact date).
I believe that if existing it should be something as
DateTime.Convert(2015.12.9, 'yyyy/MM/dd', CultureInfo.CurrentCulture).
Any ideas?
EDIT:
Thank you all for your ideas and suggestions, however the interpretation most of you gave to my question was not quite right. What most of you have answered is a direct parse in the given format and then a conversion to the CurrentCulture.
DateTime.ParseExact("2015.12.9", "yyyy.MM.dd", CultureInfo.CurrentCulture)
This will still return 12 as month, although it is in the CurrentCulture format. My question thus was, is there any standard way to transform the date in yyyy.MM.d to the format MM/dd/yyy so that the month is now in the correct place and THEN parsed it in the target culture. Such function is likely to be unexisting.

DateTime.ParseExact is what you are looking for:
DateTime parsedDate = DateTime.ParseExact("2015.12.9", "yyyy.MM.d", CultureInfo.InvariantCulture);
Or eventualy DateTime.TryParseExact if you're not confident with input string.

I know it's late but I try to explain little bit deep if you let me..
I am facing a problem in which I need to transform dates in any format
to a target one.
There no such a thing as dates in any format. A DateTime does not have any implicit format. It just has date and time values. Looks like you have a string which formatted as date and you want to convert another string with different format.
Is there any standard way to do this in C#?
Yes. You can parse your string with DateTime.ParseExact or DateTime.TryParseExact first with specific format to DateTime and then generate it's string representation with a different format.
As an example say we have yyyy.MM.dd as the source format and the
target format is MM/dd/yyy (current culture).
I didn't understand what is the meaning of current culture in this sentences and I assume you want yyyy not yyy, but you can generate it as I described above like;
string source = "2015.12.9";
DateTime dt = DateTime.ParseExact(source, "yyyy.MM.d", CultureInfo.InvariantCulture);
string target = dt.ToString("MM/dd/yyyy", CultureInfo.InvariantCulture); // 12/09/201
The problem arises since I am using a parsing strategy that gives
priority to the current culture and then if it fails it tries to parse
from a list of known formats.
Since you didn't show any parsing strategy and there is no DateTime.Convert method in .NET Framework, I couldn't any comment.
Now say we have two equivalent dates one in the source culture above
(2015.12.9) and the other in the current culture (9/12/2015). Then if
we attempt to parse this two dates the month will be 12 and in the
second will be 9, so we have an inconsistency.
Again.. You don't have DateTime's. You have strings. And those formatted strings can't belong on any culture. Sure all cultures might parse or generate different string representations with the same format format a format does not belong any culture.
I assume you have 2 different string which different formatted and you wanna parse the input no matter which one it comes. In such a case, you can use DateTime.TryParseExact overload that takes string array for all possible formats as a parameter. Then generate it's string representation with MM/dd/yyy format and a culture that has / as a DateSeparator like InvariantCulture.
string s = "2015.12.9"; // or 9/12/2015
string[] formats = { "yyyy.MM.d", "d/MM/yyyy" };
DateTime dt;
if (DateTime.TryParseExact(s, formats, CultureInfo.InvariantCulture,
DateTimeStyles.None, out dt))
{
Console.WriteLine(dt.ToString("MM/dd/yyyy", CultureInfo.InvariantCulture));
}

The Simple and Best way to do it is Using .ToString() Method
See this code:
DateTime x =DateTime.Now;
To Convert This Just Write like This:
x.ToString("yyyyMMdd")//20151210
x.ToString("yyyy/MM/dd)//2015/12/10
x.ToString("yyyy/MMM/dd)//2015/DEC/10 //Careful About M type should be capital for month .
Hope helpful

Why does TimeSpan.ToString() require escaping separators?

You can specify a custom format for a DateTime object like this:
DateTime.Now.ToString("HH:mm:ss"); // 19:55:23
But when I try to use the same format for a TimeSpan object like this:
DateTime.Now.TimeOfDay.ToString("HH:mm:ss");
I get the "Input string was not in a correct format." exception.
It turns out, the solution is that you need to escape the ':' characters like in "HH\\:mm\\:ss". Note that there is a double backslash because if you specify only one, it will break the string so you need to escape that one too.
The question is, why .NET Framework developers made it this way? There must be a reason for sure. Why can't we use custom format specifiers without escaping them like we can with a DateTime object?
Looking for .NET gurus to shed light on this subject.

As stated in documentation, one of the differences between DateTime.ToString and TimeSpan.ToString format specifiers is the following: the custom TimeSpan format specifiers do not include placeholder separator symbols, such as the symbols that separate days from hours, hours from minutes, or seconds from fractional seconds. Instead, these symbols must be included in the custom format string as string literals.
In contrast with TimeSpan (see table of format specifiers in docs), DateTime format specifiers include predefined symbols for Date separator /, and for Time separator :. It means that for example for Italian culture semicolon will be recognized as time separator (not the literal) and will be replaced with . symbol:
// outputs 09.57.18 instead of 09:57:18 because of Italian culture.
Console.WriteLine(DateTime.Now.ToString("hh:mm:ss", CultureInfo.GetCultureInfo("it-IT")));
I think .NET designers made such difference between DateTime and TimeSpan string formatters intentionally, and it is quite reasonable. This is because historically Date/Time were formatted differently for different cultures. And .NET tried to provide globalization means for that matter along with DateTime type. But TimeSpan did not get such 'globalization' duties, it is just a type representing period of time, and formatting of it is not tied to any culture specifics (if they are ever existed), but instead formatting of it is constant in different culture settings.

convert system date to M/d/yyyy format irrespective of system format using C#

How can I get today's date in M/d/yyyy format irrespective of system format of date using C#?
DateTime.Now.Tostring('M/d/yyyy')
is working only if the system date is in format dd/MM/yyyy or M/dd/yyyy but is not working in case yyyy-MM-dd format.
Eg:
if system date is 2013-06-26 then DateTime.Now.Tostring('M/d/yyyy') is converting the date into 06-26-2013 but not in 06/26/2013

Use CultureInfo.InvariantCulture to enforce / as date separator:
DateTime.Now.ToString("M/d/yyyy", CultureInfo.InvariantCulture)
Ideone

Looks like you just need to use CultureInfo.InvariantCulture as a second parameter in your .ToString method.
Console.WriteLine(DateTime.Now.ToString("M/d/yyyy", CultureInfo.InvariantCulture));

Using the invariant culture is the correct solution if you always want the same DateTime to produce the exact same string on multiple systems (or even on the same system due to culture changes). However, be aware that if this is user-visible, you're giving up the possibility of internationalization (for instance, if you display day or month names, they will be in English regardless of what language the user speaks). To only ensure that slashes are not replaced with another date separator, use single quotation marks:
DateTime.Now.Tostring("M'/'d'/'yyyy");
Edit:
Also, if your users are using different date formats, there's a good chance they're also using different time zones. If this DateTime needs to make sense across multiple systems, consider using DateTime.UtcNow. This will also protect you against potential bugs due to a user changing their time zone (when travelling, say) or daylight saving/summer time beginning/ending. If you're just displaying the string to the user at the current instance and not persisting it, DateTime.Now is probably what you want. In that case, however, I'd question why you're trying to mess with the format they've chosen.

Like this:
DateTime.Now.Tostring("M'/'d'/'yyyy");
The apostrofe forces the ToString() method to use the delimiter that you specified.
However, I would let the user choose a culture and use that cultures default formatting instead.