ME51N CHANGE MEREQ3320-PREIS DURING PR CREATION

Question

Dear All,
I want to change the Valuation Price in transaction ME51N.
The SAP´s standard gives me the price available in material master record but I need in MEREQ3320-PREIS last buying price of the material.
We have implemented MEREQ001 Customers' Own Data in Purchase Requisition enhancement  . and  implemented  user exit 
EXIT_SAPLMEREQ_010 but in that  we cannot modify PREIS field  which is present in IM_T_EBAN STRUCTURE  (import parameter )
Is there any other way to modify MEREQ3320-PREIS (price Valuation)  field  during  SAVE IN    ME51N .
Your help is highly appreciated.
regards
Deepak.
Edited by: Deepak Dhamat on Sep 15, 2011 6:25 AM

Answer 1

Hi  ,
Thank you all for your support   .
@Klaus  :  it was helpfull answer  but  i  changed my mind to use  BADI   .
@vinod  : Finaly i implemented  badi   as  you said  .
we are using this  for  only Display purpose     .
method .
if  sy-tcode  ='ME53N' .
DATA:
      ld_attr         TYPE string,
      ld_method       TYPE string,
      lo_obj          TYPE REF TO object,  " root object
      lo_obj_2        TYPE REF TO object.
  DATA : w_ebeln TYPE ekpo-ebeln ,
        w_netpr TYPE ekpo-netpr   .
  FIELD-SYMBOLS:
    <lo_lcl>        TYPE ANY,
    <ls_item>       TYPE mereq_item.
  CHECK ( im_count = 1 ).  " avoid endless iteration -> see NOTE below
  lo_obj     ?= im_item.  " casting to root object !!!!!
  ld_attr = 'MY_STATE'.
  ASSIGN lo_obj->(ld_attr) TO <lo_lcl>.
  ld_attr = 'MY_STATE->ITEM'.
  ASSIGN lo_obj->(ld_attr) TO <ls_item>.
  IF <ls_item>-knttp = 'K' .
    SELECT MAX( ebeln ) INTO w_ebeln FROM ekpo
       WHERE matnr = <ls_item>-matnr
        AND  werks = <ls_item>-werks  .
    IF W_EBELN IS NOT INITIAL .
      SELECT  MAX( netpr ) INTO w_netpr FROM ekpo
           WHERE ebeln = w_ebeln .
      IF W_NETPR  IS NOT INITIAL  .
        <ls_item>-preis = w_netpr  .
      ENDIF.
    ENDIF .
  ENDIF.
ENDIF.
regards
Deepak.