ABAP-MB21,MB22保存校验增强

如果想检查单行的话可以通过BADI:MB_RESERVATION_BADI，本文是检查重复物料，所以不好使用这个BADI，用了隐式增强

隐式增强位置，程序：MM07RFD0

  TYPES:
    BEGIN OF TY_MATNR,
      MATNR TYPE MARA-MATNR,
    END OF TY_MATNR.

  DATA:
    LS_MATNR  TYPE TY_MATNR,
    LT_MATNR  TYPE TABLE OF TY_MATNR.

  IF FCODE_NEXT = FCOD-BU.
    IF SY-TCODE = 'MB21'
    OR SY-TCODE = 'MB22'.
      LOOP AT YRSEG
        WHERE XLOEK <> 'X'.
        READ TABLE LT_MATNR TRANSPORTING NO FIELDS
          WITH KEY MATNR = YRSEG-MATNR.

        IF SY-SUBRC <> 0.
          LS_MATNR-MATNR = YRSEG-MATNR.
          APPEND LS_MATNR TO LT_MATNR.
        ELSE.
          MESSAGE '物料' && YRSEG-MATNR && '有重复项！' TYPE 'E'.
        ENDIF.
      ENDLOOP.
    ENDIF.
  ENDIF.