To put validatition check on date

Question

hi
there is data being loaded from a flat file i want to input check on date format as yyyymmdd format only please suggest how to put this check
regards
arora

Answer 1

If you want to understand - run the program in debug and watch what happens to the values.  Or add some more write statements like this.
PARAMETERS: p_dat TYPE c LENGTH 8.
DATA: test_date TYPE d,
      input_date TYPE d.
input_date = p_dat.
WRITE:/ 'Value of p_dat', p_dat DD/MM/YYYY.
WRITE:/ 'Value of input_date', input_date DD/MM/YYYY.
test_date = input_date - 1.
WRITE:/ 'Subtracted one from input_date to give', test_date DD/MM/YYYY.
ADD 1 TO test_date.
WRITE:/ 'Added one to test_date to give', test_date DD/MM/YYYY.
IF test_date = input_date.
  WRITE: / 'Test_date same as input_date, so the original date was valid'.
ELSE.
  WRITE: / 'Test_date NOT the same as input_date, so the original date was invalid'.
ENDIF.
If p_dat contains an invalid date, then when you subtract one from input_date it gives you '00000000' - i.e. INITIAL for a type D.
So you could rewrite the code:
PARAMETERS: p_dat TYPE c LENGTH 8.
DATA: input_date TYPE d.
input_date = p_dat.
SUBTRACT 1 FROM input_date.
IF input_date IS NOT INITIAL.
  WRITE: / 'Subtraction from input date is not blank so the original date was valid'.
ELSE.
  WRITE: / 'Subtraction from input date is blank so the original date was invalid'.
ENDIF.
matt