WinDateTimeEditor supports Japanese Calendar since 17.1.

Currently you can set only 1 calendar, so if a customer set Japanese Calendar in FormatProvider, both Edit and Display mode uses Japanese Calendar.

there's an use case requested from a customer that he wants to use default Calendar in edit mode and show Japanese calendar in display mode.

E.g: yyyy/mmdd: 2018/12/4

Edit mode: 2018/12/4

Display mode: 平成30年12月4日