Date format in C#

DateTime DateTimeDT = new DateTime(2012, 3, 9, 16, 5, 7, 123);

String.Format("{0:y yy yyy yyyy}", DateTimeDT );  
String.Format("{0:M MM MMM MMMM}", DateTimeDT );
String.Format("{0:d dd ddd dddd}", DateTimeDT );  
String.Format("{0:h hh H HH}",     DateTimeDT );  
String.Format("{0:m mm}",          DateTimeDT );
String.Format("{0:s ss}",          DateTimeDT ); 
String.Format("{0:f ff fff ffff}", DateTimeDT );
String.Format("{0:F FF FFF FFFF}", DateTimeDT );
String.Format("{0:t tt}",          DateTimeDT );
String.Format("{0:z zz zzz}",      DateTimeDT );