概述：程序的思路就是，把每个IDOC节点按字符串形式逐个添加，而字符串的添加次序自然也体现了IDOC节点间的逻辑关系。
    代码如下：

    1. DATA: ls_pohead TYPE ypohead,       "IDoc数据段：头
    2.       ls_poitem TYPE ypoitem,        "IDoc数据段：Item
    3.       ls_edidc TYPE edidc,            "IDoc的控制记录
    4.       lt_edidc TYPE TABLE OF edidc,
    5.       lt_edidd TYPE TABLE OF edidd WITH HEADER LINE.    "IDoc的数据记录
    6. CLEAR ls_edidc.
    7. *系统根据下面4行即可与WE20(合作和伴配置文件)设置关联起来
    8. ls_edidc-mestyp = 'YPO_MESS_TYPE'.     "Message Type
    9. ls_edidc-idoctp = 'YPOIDOC'.         "IDOC Type
    10. ls_edidc-rcvprn = 'Z810LS'.     "partner Number of Recipient接收方合作伙伴
    11. ls_edidc-rcvprt = 'LS'.      "partner Type of Receiver接收方类型为逻辑系统
    13. *添加IDOC节点
    14. CLEAR lt_edidd.
    15. lt_edidd-segnam = 'YPOHEAD'.        "头节点
    16. lt_edidd-dtint2 = 0.
    17. CLEAR ls_pohead.
    18. ls_pohead-ebeln = '4001122334'.        "采购单号
    19. ls_pohead-bukrs = '1000'.            "公司代码
    20. ls_pohead-bedat = '20090630'.        "日期
    21. lt_edidd-sdata = ls_pohead.         "节点内容：ls_pohead结构中的数据最后被拼接成字符串再赋值给lt_edidd-sdata，最大长度不能超过1000
    22. APPEND lt_edidd.
    24. CLEAR lt_edidd.
    25. lt_edidd-segnam = 'YPOITEM'.                "Item节点
    26. lt_edidd-dtint2 = 0.
    27. CLEAR ls_poitem.
    28. ls_poitem-ebeln = '4001122334'.                "采购单号
    29. ls_poitem-ebelp = '0001'.                    "Item行号
    30. ls_poitem-matnr = '000000000000004527'.        "物料号
    31. ls_poitem-menge = '3'.                        "数量
    32. ls_poitem-meins = 'ST'.                        "单位
    33. lt_edidd-sdata = ls_poitem.
    34. APPEND lt_edidd.
    36. CLEAR lt_edidd.
    37. lt_edidd-segnam = 'YPOITEM'.                "Item节点
    38. lt_edidd-dtint2 = 0.
    39. CLEAR ls_poitem.
    40. ls_poitem-ebeln = '4001122334'.                "采购单号
    41. ls_poitem-ebelp = '0002'.                    "Item行号
    42. ls_poitem-matnr = '000000000000009289'.        "物料号
    43. ls_poitem-menge = '5'.                        "数量
    44. ls_poitem-meins = 'M'.                        "单位
    45. lt_edidd-sdata = ls_poitem.
    46. APPEND lt_edidd.
    48. CALL FUNCTION 'MASTER_IDOC_DISTRIBUTE'            "发送IDoc
    49.   EXPORTING
    50.     master_idoc_control            = ls_edidc     "IDoc控制记录
    51.   TABLES
    52.     communication_idoc_control     = lt_edidc     "接收：用来接收IDoc发送情况
    53.     master_idoc_data               = lt_edidd     "IDoc数据记录
    54.   EXCEPTIONS"
    55.     error_in_idoc_control          = 1
    56.     error_writing_idoc_status      = 2
    57.     error_in_idoc_data             = 3
    58.     sending_logical_system_unknown = 4
    59.     OTHERS                         = 5.
    60. IF sy-subrc <> 0.
    61.   MESSAGE ID sy-msgid TYPE sy-msgty NUMBER sy-msgno
    62.           WITH sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
    63. ELSE.
    64.   COMMIT WORK.
    65.   WRITE: 'Idoc sent:'.
    66.   LOOP AT lt_edidc INTO ls_edidc.
    67.     NEW-LINE.
    68.     WRITE: 'Idoc number is', ls_edidc-docnum,
    69.            '; receiver partner is', ls_edidc-rcvprn,
    70.            '; sender partner',ls_edidc-sndprn.
    71.   ENDLOOP.
    72. ENDIF.

    参考：汪正军——IDOC-出站异步方式