ABAP中加上前导零、去除前导零的function module

PERFORM add_zero CHANGING p_in.
PERFORM del_zero CHANGING p_out.

*加上p_in的前导零

FORM add_zero CHANGING p_in.

CALL FUNCTION 'CONVERSION_EXIT_ALPHA_INPUT'
    EXPORTING
      input = p_in
    IMPORTING
utput = p_in.

ENDFORM.

*去除p_out的前导零

FORM del_zero CHANGING p_out.

CALL FUNCTION 'CONVERSION_EXIT_ALPHA_OUTPUT'
    EXPORTING
      input = p_out
    IMPORTING
     output = p_out.

ENDFORM.