Why does DateTimeInfo.MonthNames return 13 members?

Question

Possible duplicate:
GetMonthName: Valid values ​​are 1 through 13 inclusive. Why?

The following code:

DateTimeFormatInfo datetimeinfo = new CultureInfo("en-GB", false).DateTimeFormat; string[] months = datetimeinfo.MonthNames; 

returns 13 members, and 0 is January, and 13 is an empty string.

Why is this?

This doesn't really matter, as I can just delete the last member, but I'm just wondering if that makes sense.

Answer 1

Some calendars, particularly Hebrew , can have 13 months. This is usually the case in lunar polar calendars that use the lunar months, and then add an extra month every few years to avoid the beginning of a year that changes too much from the solar year.