Sets or gets the date time input format of the date.
Possible Values:
'd'-the day of the month
'dd'-the day of the month
'ddd'-the abbreviated name of the day of the week
'dddd'-the full name of the day of the week
'h'-the hour, using a 12-hour clock from 1 to 12
'hh'-the hour, using a 12-hour clock from 01 to 12
'H'-the hour, using a 24-hour clock from 0 to 23
'HH'-the hour, using a 24-hour clock from 00 to 23
'm'-the minute, from 0 through 59
'mm'-the minutes,from 00 though59
'M'-the month, from 1 through 12;
'MM'-the month, from 01 through 12
'MMM'-the abbreviated name of the month
'MMMM'-the full name of the month
's'-the second, from 0 through 59
'ss'-the second, from 00 through 59
't'-the first character of the AM/PM designator
'tt'-the AM/PM designator
'y'-the year, from 0 to 99
'yy'-the year, from 00 to 99
'yyy'-the year, with a minimum of three digits
'yyyy'-the year as a four-digit number