GS.C#: декабря 2023

воскресенье, 24 декабря 2023 г.

ConfigureAwait(false), ConfigureAwait(true),

The difference between await Task.Delay(TimeInterval).ConfigureAwait(false) and await Task.Delay(TimeInterval).ConfigureAwait(true) lies in the context in which the continuation of the method will execute.

await Task.Delay(TimeInterval).ConfigureAwait(false): This tells the runtime that the continuation doesn't need to run in the original context captured at the start of the async method. This means that the continuation can execute on any available thread, which can lead to better performance, particularly in library code that needs to avoid deadlocks. However, it also means that you cannot access any context-specific resources (like UI elements in a Windows Forms or WPF app) from within the continuation ², ⁵.

await Task.Delay(TimeInterval).ConfigureAwait(true): This tells the runtime that the continuation should run in the original context captured at the start of the async method. This means that the continuation will execute on the same thread that started the async method, and it will have access to the same context-specific resources. However, this can lead to potential deadlocks if the original context is blocked waiting for the async method to complete ², ⁵.

Using .ConfigureAwait(false) can be beneficial in scenarios where you're developing a library that will be used by other applications.

Consider the following scenario: You're developing a library that includes an asynchronous method. This method uses await to wait for an asynchronous operation to complete. Inside this method, you're using ConfigureAwait(false), which means that the rest of the method can continue running on any available thread when the awaited task completes.

Now, let's say that a developer uses your library in their application. They call your asynchronous method from their own synchronous method. Because your method is asynchronous and uses ConfigureAwait(false), it doesn't capture the original context and can complete on any thread.

This means that when your method finishes and control returns to the caller, the caller can also continue on any thread. This can help to avoid potential deadlocks that can occur if the caller was waiting for the method to complete on the original context (for example, the UI thread in a desktop application).

https://stackoverflow.com/questions/47217849/understanding-configureawait

https://habr.com/ru/articles/482354/

https://habr.com/ru/articles/721050/

https://devblogs.microsoft.com/dotnet/configureawait-faq/

https://habr.com/ru/companies/clrium/articles/463587/

суббота, 23 декабря 2023 г.

Format, DateTime

https://learn.microsoft.com/en-us/dotnet/standard/base-types/custom-date-and-time-format-strings

Format specifier	Description	Examples
"d"	The day of the month, from 1 to 31. More information: The "d" Custom Format Specifier.	2009-06-01T13:45:30 -> 1 2009-06-15T13:45:30 -> 15
"dd"	The day of the month, from 01 to 31. More information: The "dd" Custom Format Specifier.	2009-06-01T13:45:30 -> 01 2009-06-15T13:45:30 -> 15
"ddd"	The abbreviated name of the day of the week. More information: The "ddd" Custom Format Specifier.	2009-06-15T13:45:30 -> Mon (en-US) 2009-06-15T13:45:30 -> Пн (ru-RU) 2009-06-15T13:45:30 -> lun. (fr-FR)
"dddd"	The full name of the day of the week. More information: The "dddd" Custom Format Specifier.	2009-06-15T13:45:30 -> Monday (en-US) 2009-06-15T13:45:30 -> понедельник (ru-RU) 2009-06-15T13:45:30 -> lundi (fr-FR)
"f"	The tenths of a second in a date and time value. More information: The "f" Custom Format Specifier.	2009-06-15T13:45:30.6170000 -> 6 2009-06-15T13:45:30.05 -> 0
"ff"	The hundredths of a second in a date and time value. More information: The "ff" Custom Format Specifier.	2009-06-15T13:45:30.6170000 -> 61 2009-06-15T13:45:30.0050000 -> 00
"fff"	The milliseconds in a date and time value. More information: The "fff" Custom Format Specifier.	6/15/2009 13:45:30.617 -> 617 6/15/2009 13:45:30.0005 -> 000
"ffff"	The ten thousandths of a second in a date and time value. More information: The "ffff" Custom Format Specifier.	2009-06-15T13:45:30.6175000 -> 6175 2009-06-15T13:45:30.0000500 -> 0000
"fffff"	The hundred thousandths of a second in a date and time value. More information: The "fffff" Custom Format Specifier.	2009-06-15T13:45:30.6175400 -> 61754 6/15/2009 13:45:30.000005 -> 00000
"ffffff"	The millionths of a second in a date and time value. More information: The "ffffff" Custom Format Specifier.	2009-06-15T13:45:30.6175420 -> 617542 2009-06-15T13:45:30.0000005 -> 000000
"fffffff"	The ten millionths of a second in a date and time value. More information: The "fffffff" Custom Format Specifier.	2009-06-15T13:45:30.6175425 -> 6175425 2009-06-15T13:45:30.0001150 -> 0001150
"F"	If non-zero, the tenths of a second in a date and time value. More information: The "F" Custom Format Specifier.	2009-06-15T13:45:30.6170000 -> 6 2009-06-15T13:45:30.0500000 -> (no output)
"FF"	If non-zero, the hundredths of a second in a date and time value. More information: The "FF" Custom Format Specifier.	2009-06-15T13:45:30.6170000 -> 61 2009-06-15T13:45:30.0050000 -> (no output)
"FFF"	If non-zero, the milliseconds in a date and time value. More information: The "FFF" Custom Format Specifier.	2009-06-15T13:45:30.6170000 -> 617 2009-06-15T13:45:30.0005000 -> (no output)
"FFFF"	If non-zero, the ten thousandths of a second in a date and time value. More information: The "FFFF" Custom Format Specifier.	2009-06-15T13:45:30.5275000 -> 5275 2009-06-15T13:45:30.0000500 -> (no output)
"FFFFF"	If non-zero, the hundred thousandths of a second in a date and time value. More information: The "FFFFF" Custom Format Specifier.	2009-06-15T13:45:30.6175400 -> 61754 2009-06-15T13:45:30.0000050 -> (no output)
"FFFFFF"	If non-zero, the millionths of a second in a date and time value. More information: The "FFFFFF" Custom Format Specifier.	2009-06-15T13:45:30.6175420 -> 617542 2009-06-15T13:45:30.0000005 -> (no output)
"FFFFFFF"	If non-zero, the ten millionths of a second in a date and time value. More information: The "FFFFFFF" Custom Format Specifier.	2009-06-15T13:45:30.6175425 -> 6175425 2009-06-15T13:45:30.0001150 -> 000115
"g", "gg"	The period or era. More information: The "g" or "gg" Custom Format Specifier.	2009-06-15T13:45:30.6170000 -> A.D.
"h"	The hour, using a 12-hour clock from 1 to 12. More information: The "h" Custom Format Specifier.	2009-06-15T01:45:30 -> 1 2009-06-15T13:45:30 -> 1
"hh"	The hour, using a 12-hour clock from 01 to 12. More information: The "hh" Custom Format Specifier.	2009-06-15T01:45:30 -> 01 2009-06-15T13:45:30 -> 01
"H"	The hour, using a 24-hour clock from 0 to 23. More information: The "H" Custom Format Specifier.	2009-06-15T01:45:30 -> 1 2009-06-15T13:45:30 -> 13
"HH"	The hour, using a 24-hour clock from 00 to 23. More information: The "HH" Custom Format Specifier.	2009-06-15T01:45:30 -> 01 2009-06-15T13:45:30 -> 13
"K"	Time zone information. More information: The "K" Custom Format Specifier.	With DateTime values: 2009-06-15T13:45:30, Kind Unspecified -> 2009-06-15T13:45:30, Kind Utc -> Z 2009-06-15T13:45:30, Kind Local -> -07:00 (depends on local computer settings) With DateTimeOffset values: 2009-06-15T01:45:30-07:00 --> -07:00 2009-06-15T08:45:30+00:00 --> +00:00
"m"	The minute, from 0 to 59. More information: The "m" Custom Format Specifier.	2009-06-15T01:09:30 -> 9 2009-06-15T13:29:30 -> 29
"mm"	The minute, from 00 to 59. More information: The "mm" Custom Format Specifier.	2009-06-15T01:09:30 -> 09 2009-06-15T01:45:30 -> 45
"M"	The month, from 1 to 12. More information: The "M" Custom Format Specifier.	2009-06-15T13:45:30 -> 6
"MM"	The month, from 01 to 12. More information: The "MM" Custom Format Specifier.	2009-06-15T13:45:30 -> 06
"MMM"	The abbreviated name of the month. More information: The "MMM" Custom Format Specifier.	2009-06-15T13:45:30 -> Jun (en-US) 2009-06-15T13:45:30 -> juin (fr-FR) 2009-06-15T13:45:30 -> Jun (zu-ZA)
"MMMM"	The full name of the month. More information: The "MMMM" Custom Format Specifier.	2009-06-15T13:45:30 -> June (en-US) 2009-06-15T13:45:30 -> juni (da-DK) 2009-06-15T13:45:30 -> uJuni (zu-ZA)
"s"	The second, from 0 to 59. More information: The "s" Custom Format Specifier.	2009-06-15T13:45:09 -> 9
"ss"	The second, from 00 to 59. More information: The "ss" Custom Format Specifier.	2009-06-15T13:45:09 -> 09
"t"	The first character of the AM/PM designator. More information: The "t" Custom Format Specifier.	2009-06-15T13:45:30 -> P (en-US) 2009-06-15T13:45:30 -> 午 (ja-JP) 2009-06-15T13:45:30 -> (fr-FR)
"tt"	The AM/PM designator. More information: The "tt" Custom Format Specifier.	2009-06-15T13:45:30 -> PM (en-US) 2009-06-15T13:45:30 -> 午後 (ja-JP) 2009-06-15T13:45:30 -> (fr-FR)
"y"	The year, from 0 to 99. More information: The "y" Custom Format Specifier.	0001-01-01T00:00:00 -> 1 0900-01-01T00:00:00 -> 0 1900-01-01T00:00:00 -> 0 2009-06-15T13:45:30 -> 9 2019-06-15T13:45:30 -> 19
"yy"	The year, from 00 to 99. More information: The "yy" Custom Format Specifier.	0001-01-01T00:00:00 -> 01 0900-01-01T00:00:00 -> 00 1900-01-01T00:00:00 -> 00 2019-06-15T13:45:30 -> 19
"yyy"	The year, with a minimum of three digits. More information: The "yyy" Custom Format Specifier.	0001-01-01T00:00:00 -> 001 0900-01-01T00:00:00 -> 900 1900-01-01T00:00:00 -> 1900 2009-06-15T13:45:30 -> 2009
"yyyy"	The year as a four-digit number. More information: The "yyyy" Custom Format Specifier.	0001-01-01T00:00:00 -> 0001 0900-01-01T00:00:00 -> 0900 1900-01-01T00:00:00 -> 1900 2009-06-15T13:45:30 -> 2009
"yyyyy"	The year as a five-digit number. More information: The "yyyyy" Custom Format Specifier.	0001-01-01T00:00:00 -> 00001 2009-06-15T13:45:30 -> 02009
"z"	Hours offset from UTC, with no leading zeros. More information: The "z" Custom Format Specifier.	2009-06-15T13:45:30-07:00 -> -7
"zz"	Hours offset from UTC, with a leading zero for a single-digit value. More information: The "zz" Custom Format Specifier.	2009-06-15T13:45:30-07:00 -> -07
"zzz"	Hours and minutes offset from UTC. More information: The "zzz" Custom Format Specifier.	2009-06-15T13:45:30-07:00 -> -07:00
":"	The time separator. More information: The ":" Custom Format Specifier.	2009-06-15T13:45:30 -> : (en-US) 2009-06-15T13:45:30 -> . (it-IT) 2009-06-15T13:45:30 -> : (ja-JP)
"/"	The date separator. More Information: The "/" Custom Format Specifier.	2009-06-15T13:45:30 -> / (en-US) 2009-06-15T13:45:30 -> - (ar-DZ) 2009-06-15T13:45:30 -> . (tr-TR)
"string" 'string'	Literal string delimiter. More information: Character literals.	2009-06-15T13:45:30 ("arr:" h:m t) -> arr: 1:45 P 2009-06-15T13:45:30 ('arr:' h:m t) -> arr: 1:45 P
%	Defines the following character as a custom format specifier. More information:Using Single Custom Format Specifiers.	2009-06-15T13:45:30 (%h) -> 1
\	The escape character. More information: Character literals and Using the Escape Character.	2009-06-15T13:45:30 (h \h) -> 1 h
Any other character	The character is copied to the result string unchanged. More information: Character literals.	2009-06-15T01:45:30 (arr hh:mm t) -> arr 01:45 A