创建会计凭证：BAPI_ACC_DOCUMENT

创建会计凭证：BAPI_ACC_DOCUMENT_POST 增强字段

在ABAP程序中使用BAPI_ACC_DOCUMENT_POST的时候，如果有些字段在Tables参数中没有，比如，现在大家都用Reason code来作为现金流量表的表现方案。但是在BAPI_ACC_DOCUMENT_POST的accountgl参数是没有原因代码这个字段的，这种情况下，如何能在导入凭证的时候，包括这个字段呢？毫无疑问：使用增强来实现

一、简介

首先定义一个包括POSNR(类型为POSNR_ACC) 和**RSTGR(原因代码)**两个字段。POSNR这个字段必须有，因为在BAPI_ACC_DOCUMENT_POST中会包含多个tables参数，所以需要使用行项目号来关联。比如第一行#1的总账科目、金额、extensions等。
SE19实现BADI增强ACC_DOCUMENT,这个增强是用来将BAPI_ACC_DOCUMENT_POST参数表EXTENSION2传入系统表ACCIT。只需要实现change方法
在BAPI_ACC_DOCUMENT_POST 中，启用 extension2 参数，将扩展字段传入

二、定义结构

事务码SE11定义一个结构ZSACC，包括POSNR (类型为 POSNR_ACC ) 和 RSTGR (原因代码) 两个字段。

通过BADI将扩展字段传入系统表

SE19，使用 Classical BADI，BADI name 为 ACC_DOCUMENT，点击 Create 按钮。
系统弹出如下对话框，输入implementation name:
点击确认后，进入如下界面，下面有一个Filter Values，添加一行，选择BKPFF，表示这个BADI实现只适合用于会计凭证直接输入。(根据需要添加对应的选项即可)
点击激活按钮，系统提示migrate到New Badi.并弹出如下对话款
然后我们不选择已有的 Enhancement Implementation，自己新建一个。Composite Enhancement Implementation 留空

确认后，系统提示 Activate 成功。点击界面上的 Interface 按钮，可以看到，这个 BADI 的实现有两个方法，其中 CHANGE 方法就是我们需要实现的方法，这个方法可以从 Example implementation class 拷贝，完全不用改动

  method if_ex_acc_document~change.

    data: wa_extension   type bapiparex,
          ext_value(960) type c,
          wa_accit       type accit,
          l_ref          type ref to data.

    field-symbols: <l_struc> type any,
                   <l_field> type any.

    sort c_extension2 by structure.

    loop at c_extension2 into wa_extension.
      at new structure.
        create data l_ref type (wa_extension-structure).
        assign l_ref->* to <l_struc>.
      endat.
      concatenate wa_extension-valuepart1 wa_extension-valuepart2
                  wa_extension-valuepart3 wa_extension-valuepart4
             into ext_value.
      move ext_value to <l_struc>.
      assign component 'POSNR' of structure <l_struc> to <l_field>.
      read table c_accit with key posnr = <l_field>
            into wa_accit.
      if sy-subrc is initial.
        move-corresponding <l_struc> to wa_accit.
        modify c_accit from wa_accit index sy-tabix.
      endif.
    endloop.

  endmethod.

增强实现后只要在编写程序中导入数据时写入对应的参数，案例完整代码如下

三、完整代码

report zdemo001.

data:
  docheader      like bapiache09, " structure of document header
  accountgl      like bapiacgl09 occurs 0 with header line, " internal table for glaccounts
  currencyamount like bapiaccr09 occurs 0 with header line, " internal table for currency
  return         like bapiret2   occurs 0 with header line. " internal table for return

" Extension2
data: extension2 type standard table of bapiparex with header line,
      gs_zext2   like zext2.

" Populate required values
data: l_cocd    type bukrs value 'Z900',
      l_curr    type bapiaccr09-currency value 'CNY',
      l_doctype type bapiache09-doc_type value 'SA',
      l_extname type string value 'ZEXT2'.

start-of-selection.
  perform populate_doc_header.
  perform populate_gl_accounts.
  perform populate_currency_amt.
  perform populate_extension2.
  perform generate_fi_document.

form populate_doc_header.
  clear docheader.
  docheader-username = sy-uname.
  docheader-header_txt = 'Test FI doc using BAPI'.
  docheader-comp_code = l_cocd.  " company code
  docheader-doc_date = sy-datum.
  docheader-pstng_date = sy-datum.
  docheader-doc_type = l_doctype.
endform.

form populate_gl_accounts.
  clear accountgl.

  accountgl-itemno_acc = '1'.
  accountgl-gl_account = '0010010100'.
  accountgl-comp_code = l_cocd.
  accountgl-pstng_date = sy-datum.
  accountgl-doc_type = l_doctype.
  accountgl-item_text = '银行取现'.
  append accountgl.

  clear accountgl.
  accountgl-itemno_acc = '2'.
  accountgl-gl_account = '0010020100'.
  accountgl-comp_code = l_cocd.
  accountgl-pstng_date = sy-datum.
  accountgl-value_date = sy-datum.
  accountgl-doc_type = l_doctype.
  accountgl-item_text = '银行取现'.
  append accountgl.
endform.

form populate_currency_amt.
  clear currencyamount.
  currencyamount-itemno_acc = '1'.
  currencyamount-currency = l_curr.
  currencyamount-amt_doccur = '100.00'.
  append currencyamount.

  clear currencyamount.
  currencyamount-itemno_acc = '2'.
  currencyamount-currency = l_curr.
  currencyamount-amt_doccur = '-100.00'.
  append currencyamount.
endform.

form populate_extension2.
  clear gs_zext2.
  gs_zext2-posnr = '1'.
  gs_zext2-rstgr = 'A01'.

  clear extension2.
  extension2-structure = l_extname.
  extension2-valuepart1 = gs_zext2.
  append extension2.

  clear gs_zext2.
  gs_zext2-posnr = '2'.
  gs_zext2-rstgr = 'A01'.

  clear extension2.
  extension2-structure = l_extname.
  extension2-valuepart1 = gs_zext2.
  append extension2.
endform.

form generate_fi_document.
  data: has_error    type c,
        message_line type string.
  has_error = space.

  call function 'BAPI_ACC_DOCUMENT_CHECK'
    exporting
      documentheader = docheader
    tables
      accountgl      = accountgl
      currencyamount = currencyamount
      extension2     = extension2
      return         = return.

  loop at return.
    if return-type = 'E'.
      has_error = 'X'.
      exit.
    endif.
  endloop.

  if has_error = 'X'.
    loop at return.
      concatenate return-id return-number ': ' return-message into message_line.
      write: / message_line.
      clear return.
    endloop.
  endif.

  check has_error = space.
  clear return[].

  call function 'BAPI_ACC_DOCUMENT_POST'
    exporting
      documentheader = docheader
    tables
      accountgl      = accountgl
      currencyamount = currencyamount
      extension2     = extension2
      return         = return.

  if sy-subrc is initial.
    call function 'BAPI_TRANSACTION_COMMIT'
      exporting
        wait = 'X'.

    " write messages
    loop at return.
      concatenate return-id return-number ': ' return-message into message_line.
      write: / message_line.
      clear return.
    endloop.
  endif.

  if sy-subrc is initial.
    write: / 'Successful'.
  endif.

endform.