如何实现一个BTE

Example Business Scenario for Business Transaction Events
Company A would like to copy the group key field from the vendor master into the allocation field on all the line items within a vendor invoice and payments, including the vendor lines. This requirement assumes only one vendor is posted to in a document.

To accomplish this requirement, Company A will use the Business Transaction Event 1130, Post Document: SAP Internal Field Substitution.

1. IMG Menu Path: Financial Accounting Financial Accounting Global Settings Use Business Transaction Events Environment Infosystem (Processes).
2. Find the correct Business Event. You are updating a field, so you select the Processes Info System instead of the Publish and Subscribe Info System.
3. Execute the search with the defaults.
4. Find the correct interface for updating a document: Post Document: SAP- Internal Field Substitution
5. Put your cursor on the event and click on the Sample Function Module button.
6. You are now in transaction SE37 – Function Builder. This is the function module (sample_process_00001130) you will need to copy into a "Z" name function module for your coding
7. Click on the Copy button.
8. Enter the "Z" function module name in the To Function Module field
9. Enter a Function Group. If you need to create a "Z" function group, go to transaction code SE37 and follow menu path: Go to Function Groups Create Group. A function group is a logical grouping of function modules, and the ABAP code is generated for function groups. You will be prompted for a development class and transport when creating the function group.
10. In Function Builder (transaction SE37), enter the new "Z" function module. Click on the Change button.
11. The system will default into the source code screen where you may enter your ABAP code.
12. Notice the tables available for the code. Additional tables may be declared if necessary.
13. Enter the following source code 

 tables: lfa1.
data: z_groupkey like lfa1-konzs.
z_groupkey = ' '.
loop at t_bseg.
* check for vendor lines. If one is found, read the vendor master and
* retrieve the group key field.
if t_bseg-koart eq 'K'.
select single konzs from lfa1 into z_groupkey
where lifnr = t_bseg-lifnr.
endif.
* Move the group key field into all line items allocation field.
loop at t_bsegsub.
t_bsegsub-zuonr = z_groupkey.
modify t_bsegsub index sy-tabix.
endloop. "t_bsegsub
endloop. "t_bseg

14. Save the function module.
15. Back out to the main Function Builder screen by clicking on the green arrow button.
16. Activate the function module by clicking on the Activate button
17. Assign the function module to the event in the IMG: Financial Accounting Financial Accounting Global Settings Business Transaction Events Settings Process Function Modules of an SAP Appl.
18. Hit enter past the warning messages that this is SAP data.
19. Click on the New Entries button.
20. Enter the process for your interface. In your example it is 00001130.
21. Enter the country the interface is valid for. If it is valid for all countries, leave this field blank.
22. Enter the application the interface should be called for. If it should be called for all applications, leave this field blank. Please note that not all integrated transactions are programmed to go through these interfaces! You will need to test to find out!
23. Enter the new "Z" function module
24. Save the settings. At this point you will be prompted for a CTS number for the configuration change.
25. The Business Transaction Event is complete! You are ready for testing 

相关TCODE：

BERP
FIBF

相关连接：
http://help.sap.com/saphelp_erp2005/helpdata/en/3b/7f3e8be57c11d1951f0000e82dec10/frameset.htm
http://help.sap.com/saphelp_erp2005/helpdata/en/ad/fc5a4064b4ef6fe10000000a1550b0/frameset.htm
Example：http://fuller.mit.edu/user_exits/business_transaction_event.htm
http://www.workflowbook.com/TransactionIndex.pdf