Exit or BAdI - allow/disallow to change material desc

Question

hi all experts
pls you advise me for any Exit and/or BAdI that you have experience like my case
i would like to allow or disallow to change material description in short text field at follow t-code ::
ME51N – Create Purchase Requisition
ME52N – Change Purchase Requisition
ME21N – Create Purchase Order
ME22N – Change Purchase Order
IW31 – Create Maintenance Order
IW32 – Change Maintenance Order
CJ20N – Project Builder
thanks

Answer 1

execute the below program, it will display all the exits for each transaction.
*& Report  ZUSEREXITS
REPORT  ZUSEREXITS.
TABLES : tstc, tadir, modsapt, modact, trdir, tfdir, enlfdir.
TABLES : tstct.
DATA : jtab LIKE tadir OCCURS 0 WITH HEADER LINE.
DATA : field1(30).
DATA : v_devclass LIKE tadir-devclass.
PARAMETERS : p_tcode LIKE tstc-tcode OBLIGATORY.
SELECT SINGLE * FROM tstc WHERE tcode EQ p_tcode.
IF sy-subrc EQ 0.
  SELECT SINGLE * FROM tadir WHERE pgmid = 'R3TR'
  AND object = 'PROG'
  AND obj_name = tstc-pgmna.
  MOVE : tadir-devclass TO v_devclass.
  IF sy-subrc NE 0.
    SELECT SINGLE * FROM trdir WHERE name = tstc-pgmna.
    IF trdir-subc EQ 'F'.
      SELECT SINGLE * FROM tfdir WHERE pname = tstc-pgmna.
      SELECT SINGLE * FROM enlfdir WHERE funcname =
      tfdir-funcname.
      SELECT SINGLE * FROM tadir WHERE pgmid = 'R3TR'
      AND object = 'FUGR'
      AND obj_name EQ enlfdir-area.
      MOVE : tadir-devclass TO v_devclass.
    ENDIF.
  ENDIF.
  SELECT * FROM tadir INTO TABLE jtab
  WHERE pgmid = 'R3TR'
  AND object = 'SMOD'
  AND devclass = v_devclass.
  SELECT SINGLE * FROM tstct WHERE sprsl EQ sy-langu AND
  tcode EQ p_tcode.
  FORMAT COLOR COL_POSITIVE INTENSIFIED OFF.
  WRITE:/(19) 'Transaction Code - ',
  20(20) p_tcode,
  45(50) tstct-ttext.
  SKIP.
  IF NOT jtab[] IS INITIAL.
    WRITE:/(95) sy-uline.
    FORMAT COLOR COL_HEADING INTENSIFIED ON.
    WRITE:/1 sy-vline,
    2 'Exit Name',
    21 sy-vline ,
    22 'Description',
    95 sy-vline.
    WRITE:/(95) sy-uline.
    LOOP AT jtab.
      SELECT SINGLE * FROM modsapt
      WHERE sprsl = sy-langu AND
      name = jtab-obj_name.
      FORMAT COLOR COL_NORMAL INTENSIFIED OFF.
      WRITE:/1 sy-vline,
      2 jtab-obj_name HOTSPOT ON,
      21 sy-vline ,
      22 modsapt-modtext,
      95 sy-vline.
    ENDLOOP.
    WRITE:/(95) sy-uline.
    DESCRIBE TABLE jtab.
    SKIP.
    FORMAT COLOR COL_TOTAL INTENSIFIED ON.
    WRITE:/ 'No of Exits:' , sy-tfill.
  ELSE.
    FORMAT COLOR COL_NEGATIVE INTENSIFIED ON.
    WRITE:/(95) 'No User Exit exists'.
  ENDIF.
ELSE.
  FORMAT COLOR COL_NEGATIVE INTENSIFIED ON.
  WRITE:/(95) 'Transaction Code Does Not Exist'.
ENDIF.
AT LINE-SELECTION.
  GET CURSOR FIELD field1.
  CHECK field1(4) EQ 'JTAB'.
  SET PARAMETER ID 'MON' FIELD sy-lisel+1(10).
  CALL TRANSACTION 'SMOD' AND SKIP FIRST SCREEN.
Message was edited by:
        tom tom