有关Data的Function

1、年月日相加減
Date +/- year/month/day (into the future/past)
CALL FUNCTION 'RP_CALC_DATE_IN_INTERVAL'
EXPORTING
date = l_date
days = '00'
months = p_month
signum = '-'
years = '00'
IMPORTING
calc_date = l_date.
date为输入的日期，months要加或減的月份，也可以用days or years，signum为运算符号?..

2、得到本日是第几周
Returns week for a date
*---> get week number
CALL FUNCTION 'DATE_GET_WEEK'
EXPORTING
date = in_budat
IMPORTING
week = l_week
EXCEPTIONS
date_invalid = 1
OTHERS = 2.

3、得到本周的第一天
Return first day for a week
*---> get first day of week
CALL FUNCTION 'WEEK_GET_FIRST_DAY'
EXPORTING
week = l_week
IMPORTING
date = it_week-week_dt
EXCEPTIONS
week_invalid = 1
OTHERS = 2.

4、得到本日是本星期的第几天
CALL FUNCTION 'DAY_IN_WEEK'
EXPORTING
datum = p_date1
IMPORTING
wotnr = l_day.

5、Check 传入日期是否正确
Date plausibility check
CALL FUNCTION 'DATE_CHECK_PLAUSIBILITY'
EXPORTING
date = it_excel-redat
EXCEPTIONS
plausibility_check_failed = 1
OTHERS = 2.
IF sy-subrc <> 0.
it_err-ecode = '10'.
it_err-evalue = it_excel-redat.
it_err-ereason = 'Release Date is not valid'.
APPEND it_err.
endif.