sap abap在表VBAP和VBAK上增加新字段的标准BAPI

在表VBAP和VBAK上增加新字段的标准BAPI 
If you have custom ZZ fields on VBAP and VBAK then you can update these fields using the standard BAPI to create or change the order and update these fields.
A lot has been spoken about this but nowhere does it spell out the pitfalls and give you an end-to-end procedure on how to do it. I even found some "SAP Experts - Ask
a question" on Search SAP give a complete wrong answer!!! So here is the correct way to do it.
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To do so you first need to ensure that the following 5 tables are in synch.
1) VBAP: In your append structure you specify your ZZFIELD with the data type as needed
2) BAPE_VBAP:
In the append structure here also add the ZZFIELD with the data type as needed with limitations. No decimals. Try and stick to char characters
3) BAPE_VBAPX:
In the append structure add the field ZZFIELD of type BAPIUPDATE
(NOTE: (2) and (3) must have the same number of fields in the same order)
4) VBAPKOZ: In the append structure here also add the ZZFIELD with the data type as needed with limitations. No decimals. Try and stick to char characters
5) VBAPKOZX: In the append structure add the field ZZFIELD of type BAPIUPDATE
(NOTE: (4) and (5) must have the same number of fields in the same order)
Similarly do for VBAK, BAPE_VBAK, BAPE_VBAKX,
VBAKKOZ and VBAKKOZX.
Next we get to the code to fill in the structure EXTENSIONIN
I will demonstrate how to call the create sales order BAPI with custom fields.
* Local definitions
  DATA: wa_extensionin
TYPE bapiparex,
        wa_bape_vbap 
 TYPE bape_vbap,
        wa_bape_vbapx  TYPE bape_vbapx,
        wa_bape_vbak 
 TYPE bape_vbak,
        wa_bape_vbakx  TYPE bape_vbakx,
        lv_posnr 
     TYPE posnr.
* Processing the header extension
  CLEAR wa_bape_vbak.
  wa_bape_vbak-ZZFIELD 
   = 'HDRTEST'.
  wa_extensionin-structure
= 'BAPE_VBAK'.
  wa_extensionin+30(960) 
 = wa_bape_vbak.
  append wa_extensionin
to lt_extensionin.
  clear wa_extensionin.
* Processing the line extension
LOOP AT line_items
INTO wa_lineitems.
  ADD 10 TO lv_posnr. 
 
  CLEAR wa_bape_vbap.
  wa_bape_vbap-ZZFIELD 
   = 'TEST'.
  wa_extensionin-structure
= 'BAPE_VBAP'.
  wa_bape_vbap-posnr 
     = lv_posnr.
  wa_extensionin+30(960) 
 = wa_bape_vbap.
  append wa_extensionin
to lt_extensionin.
  clear wa_extensionin.
  CLEAR wa_bape_vbapx.
  wa_bape_vbapx-ZZFIELD 
  = 'X'.
  wa_extensionin-structure
= 'BAPE_VBAPX'.
  wa_bape_vbapx-posnr 
    = lv_posnr.
  wa_extensionin+30(960) 
 = wa_bape_vbapx.
  append wa_extensionin
to lt_extensionin.
  clear wa_extensionin.
ENDLOOP.
* Then the call to the BAPI
      CALL FUNCTION 'BAPI_SALESORDER_CREATEFROMDAT2'
        EXPORTING
          order_header_in  =
ls_order_header_in
          order_header_inx
= ls_order_header_inx
        IMPORTING
          salesdocument    = lv_salesdocument
        TABLES
          return           = lt_ret2
          order_items_in 
 = lt_order_items_in
          order_items_inx  =
lt_order_items_inx
          order_partners 
 = lt_order_partners
          order_keys 
     = lt_order_keys
          extensionin      = lt_extensionin.
Note: If you have a need to force a different Business Object type or wish to see the extension return fields then use the function SD_SALESDOCUMENT_CREATE
instead.
      CALL FUNCTION 'SD_SALESDOCUMENT_CREATE'
        EXPORTING
          sales_header_in 
   = ls_order_header_in
          sales_header_inx 
  = ls_order_header_inx
          business_object 
   = 'BUS2032'
        IMPORTING
          salesdocument_ex 
  = lv_salesdocument
          sales_header_out 
  = lv_sales_header_out
          sales_header_status
= lv_sales_header_status
        TABLES
          return              = lt_ret2
          sales_items_in 
    = lt_order_items_in
          sales_items_inx 
   = lt_order_items_inx
          sales_partners 
    = lt_order_partners
          sales_keys 
        = lt_order_keys
          extensionin         = lt_extensionin
          incomplete_log 
    = lt_incomplete_log
          extensionex         = lt_extensionex.