field symbol动态分配的妙用：在出口中访问其他程序中字段的值

DATA: LV_AUTH LIKE USRBF2-AUTH.
DATA: LV_VON  LIKE UST12-VON.
*{   INSERT         PRDK900214                                        1
DATA: lv_zuonr TYPE dzuonr.
FIELD-SYMBOLS: TYPE dzuonr,
               TYPE prctr.
DATA: c_invfo(21) TYPE c VALUE '(SAPLFDCB)INVFO-ZUONR'.
DATA: c_alloc_num(17) TYPE c VALUE
                      '(ZPCFIE08)P_PRCTR'.

  ASSIGN (c_invfo) TO .
  IF sy-subrc = 0.
    lv_zuonr = .
  ELSE.
    ASSIGN (c_alloc_num) TO .
    IF sy-subrc = 0.
      lv_zuonr = .
    ENDIF.
  ENDIF.