c# datetime format
// create date time 2008-03-09 16:05:07.123
DateTime dt = new DateTime(2008, 3, 9, 16, 5, 7, 123);
$"{dt:y yy yyy yyyy}"; // "8 08 008 2008" year
$"{dt:M MM MMM MMMM}"; // "3 03 Mar March" month
$"{dt:d dd ddd dddd}"; // "9 09 Sun Sunday" day
$"{dt:h hh H HH}"; // "4 04 16 16" hour 12/24
$"{dt:m mm}"; // "5 05" minute
$"{dt:s ss}"; // "7 07" second
$"{dt:f ff fff ffff}"; // "1 12 123 1230" sec.fraction
$"{dt:F FF FFF FFFF}"; // "1 12 123 123" without zeroes
$"{dt:t tt}"; // "P PM" A.M. or P.M.
$"{dt:z zz zzz}"; // "-6 -06 -06:00" time zone
// month/day numbers without/with leading zeroes
$"{dt:M/d/yyyy}"; // "3/9/2008"
$"{dt:MM/dd/yyyy}"; // "03/09/2008"
// day/month names
$"{dt:ddd, MMM d, yyyy}"; // "Sun, Mar 9, 2008"
$"{dt:dddd, MMMM d, yyyy}"; // "Sunday, March 9, 2008"
// two/four digit year
$"{dt:MM/dd/yy}"; // "03/09/08"
$"{dt:MM/dd/yyyy}"; // "03/09/2008"