Implementing and Debugging User Exits: Function Module in SAP Sales Order (VA01)

[dave04]

Implementing User Exits in SAP Sales Order (VA01)

Definition and Purpose
User exits are predefined enhancement points in SAP that allow developers to insert custom logic without modifying the standard code. They ensure system flexibility while maintaining compatibility with future updates.

Types of User Exits:
🔹Menu Exits – Add custom menu items for navigation (e.g., linking a custom report in the sales order menu).
🔹Function Module Exits – Insert custom validation or modify data before saving (e.g., validating sales order inputs).
🔹Screen Exits – Add custom fields to SAP screens (e.g., extending customer master data screens).

Implementation Example: Function Module
Using USEREXIT_SAVE_DOCUMENT_PREPARE, we enforce a minimum order quantity in VA01 to ensure data accuracy.

Read more to optimize your SAP workflow.

Implementing User Exits: Function

For this example, we want to create a sales document using VA01 transaction code, but we set the minimum quantity that the user input as 100.

• Go to VA01 transaction code

• Fill in the Order Type based on your requirement, but in this case we just fill in with OR or a standard order, then press Enter
• So, our purpose is to make Order Quantity have a minimum value

If the user doesn't input the Order Quantity according to the minimum limit, the user will get a message.

• Now we want to find the related user exit to add our logic, by clicking System > Status

• Then double-click the Program (screen) name

• We will jump into the SAPMV45A program

• Press Display Object List
• 

1. Go to Subroutines and find the subroutine that is related to the user's exits by finding the subroutines that start with USEREXIT

• Choose USEREXIT_SAVE_DOCUMENT_PREPARE

• We will set our logic here

• To find the spot that we can edit, Go to Edit >  Enhancements operations > Show Implicit Enhancement Options

• Then press Enhancement

• At the end of the form USEREXIT_SAVE_DOCUMENT_PREPARE right-click then press Enhancement operations > Create Implementation

• Choose Code

• Create new Implementation

• Put this code inside the Enhancement Implementation.

ABAP
  data: lv_flag TYPE boolean.

   CLEAR lv_flag.
   IF sy-UNAME = ''. "fill in with your user name
     LOOP AT xvbap INTO DATA(ls_xvbap) WHERE updkz ne 'D'.
       IF ls_xvbap-KWMENG < '100.000'.
         MESSAGE 'The quantity must be higher than 100' TYPE 'I'.
         lv_flag = 'X'.
         exit.
       ENDIF.
     ENDLOOP.

     IF lv_flag = 'X'.
       leave to SCREEN sy-DYNNR.
     ENDIF.

   ENDIF.

• Add debug in line

• Click Direct processing
• Input sales order OR

• Add data, then click save

• Abab debug will be displayed, the click continue’

• Error message will be displayed. it means, user exit is developed successfully.

[DafinaZahra]

thanks for sharing!