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DATA : BEGIN OF ITAB OCCURS 0,
         A(100) TYPE C,
       END OF ITAB.

DATA: XML_OUT TYPE STRING .

*------------------- XML
CALL TRANSFORMATION ('ID')
SOURCE TAB = T001[]   <-- xml로 형태로 바꾸고 싶은 인터널데이터
RESULT XML XML_OUT.

*------------- Convert to TABLE

CALL FUNCTION 'HR_EFI_CONVERT_STRING_TO_TABLE'
  EXPORTING
    I_STRING         = XML_OUT
    I_TABLINE_LENGTH = 100
  TABLES
    ET_TABLE         = ITAB.   <-- 인터널 xml데이타

아래 프로그램 참고하세요.

REPORT ZDOWNXML  LINE-SIZE 132 NO STANDARD PAGE HEADING.
* Databases
TABLES: MAKT,  "Mat description
        MARC,   "Material / plant
        T001W,  "plant name
        BHDGD.   "Batch heading

* Internal tables
DATA: BEGIN OF I_MARC OCCURS 0,
      WERKS  LIKE MARC-WERKS,
      MATNR  LIKE MARC-MATNR.
DATA: END OF I_MARC.

* Table to be downloaded as xml. Each line stores start and end tags
* and the value
DATA: BEGIN OF XML OCCURS 0,
      LINE(80) TYPE C.
DATA: END OF XML.

* User-input
SELECT-OPTIONS: S_WERKS FOR MARC-WERKS,
                S_MATNR FOR MARC-MATNR.

************************************************************************
START-OF-SELECTION.
************************************************************************

* Extract all required data
  PERFORM MAIN_PROCESSING.

************************************************************************
END-OF-SELECTION.
************************************************************************
  SORT I_MARC BY WERKS MATNR.
  LOOP AT I_MARC.

      AT FIRST.                           "First tag must be root
        CLEAR XML.
        XML-LINE = '<LOCATIONS>'.
        APPEND XML.
        CLEAR XML.
      ENDAT.

      AT NEW WERKS.                       "At new plant
        PERFORM READ_PLANT.
        FORMAT COLOR 4 ON.
        SKIP 1.
        WRITE :/ I_MARC-WERKS, T001W-NAME1.
        FORMAT COLOR 4 OFF.
        CLEAR XML.
        XML-LINE = ' <PLANT>'.
        APPEND XML.
        CLEAR XML.
        CONCATENATE ' <NUMBER>' I_MARC-WERKS '</NUMBER>'
                            INTO XML-LINE.
        APPEND XML.
        CLEAR XML.
        CONCATENATE ' <NAME>' T001W-NAME1 '</NAME>' INTO XML-LINE.
        APPEND XML.
        CLEAR XML.
        XML-LINE = ' </PLANT>'.
        APPEND XML.
        CLEAR XML.

      ENDAT.

       PERFORM READ_DESCRIPTION.

       CLEAR XML.
       XML-LINE =  ' <MATERIAL>'.
       APPEND XML.
       CLEAR XML.
       CONCATENATE ' <NAME>' MAKT-MAKTX '</NAME>'
                   INTO XML-LINE.
       APPEND XML.
       CLEAR XML.
       CONCATENATE ' <NUMBER>' I_MARC-MATNR '</NUMBER>'
                   INTO XML-LINE.
       APPEND XML.
       CLEAR XML.
       XML-LINE =  ' </MATERIAL>'.
       APPEND XML.
       CLEAR XML.

* display data
        FORMAT COLOR 2 ON.
        WRITE :/ I_MARC-MATNR, MAKT-MAKTX.
        FORMAT COLOR 2 OFF.
  ENDLOOP.

*-- The last tag must be the root closing tag --*
     XML-LINE = '<LOCATIONS>'.
     APPEND XML.
     CLEAR XML.

     CALL FUNCTION 'DOWNLOAD'
     EXPORTING
       FILENAME = 'C:PLANT1.XML'
       FILETYPE = 'ASC'
     TABLES
       DATA_TAB = XML.


************************************************************************
TOP-OF-PAGE.
************************************************************************
    MOVE SY-TITLE TO BHDGD-LINE1.
    MOVE SY-REPID TO BHDGD-REPID.
    MOVE SY-UNAME TO BHDGD-UNAME.
    MOVE SY-DATUM TO BHDGD-DATUM.
    MOVE '0'      TO BHDGD-INIFL.
    MOVE '132'    TO BHDGD-LINES.

    FORMAT INTENSIFIED ON COLOR COL_HEADING.
    PERFORM BATCH-HEADING(RSBTCHH0).   "report header
*&---------------------------------------------------------------------*
*& Form READ_PLANT
*&---------------------------------------------------------------------*
FORM READ_PLANT.

* Get plant name
    CLEAR T001W.
    SELECT  SINGLE NAME1
      INTO T001W-NAME1
      FROM  T001W
      WHERE WERKS EQ I_MARC-WERKS.

ENDFORM.                    " READ_PLANT
*&---------------------------------------------------------------------*
*& Form MAIN_PROCESSING
*&---------------------------------------------------------------------*
FORM MAIN_PROCESSING.

* Material and plant basic data
  SELECT  WERKS MATNR
    INTO TABLE I_MARC
    FROM  MARC
    WHERE WERKS IN S_WERKS
    AND   MATNR IN S_MATNR.

ENDFORM.                    " MAIN_PROCESSING
*&---------------------------------------------------------------------*
*& Form READ_DESCRIPTION
*&---------------------------------------------------------------------*
FORM READ_DESCRIPTION.

* Material name
    CLEAR MAKT.
    SELECT  SINGLE MAKTX
      INTO  MAKT-MAKTX
      FROM  MAKT
      WHERE  MATNR EQ I_MARC-MATNR
      AND    SPRAS EQ 'E'.

ENDFORM.                    " READ_DESCRIPTION

위의 두분의 방법을 사용해도 되고, parsing하는 class가 있습니다.

xml로 검색해서 찾아보세요. 예전에 다른 분이 올리신 글이 있습니다.

string은 문자열이고, xstring은 binary 값입니다.

길이 제한은 둘 다 없습니다.