How to determine structure of an Internal table dynamically ?

Question

Dear Friends,
On the selection screen.. I have a parameter to pass a structure (eg. E1MARAM ) in to program . Now the challenge is  to create an internal table with the structure that is passed from the selection screen(here eg.E1MARAM)
Please help me out..

Answer 1

Hello,
I had a similar situation where i did not know what the table name would be or the structure name would and this is how i created it.
*--Data Declaration.
  FIELD-SYMBOLS : <i_temp> TYPE ANY TABLE,
                  <wa_temp> TYPE ANY,
                  <fs_begru> TYPE ANY.
**Internal table for getting structure of table obtained at run-time
  DATA: BEGIN OF nametab OCCURS 0.
          INCLUDE STRUCTURE dntab.
  DATA: END OF nametab.
**Move the Class table name obtained at run-time
  MOVE dynamic-tabname TO tabname.
**Calling function to get the structure of the table name passed as
**exporting parameter
  CALL FUNCTION 'NAMETAB_GET'
       EXPORTING
            langu               = sy-langu
            tabname             = tabname
       TABLES
            nametab             = nametab
       EXCEPTIONS
            internal_error      = 1
            table_has_no_fields = 2
            table_not_activ     = 3
            no_texts_found      = 4
            OTHERS              = 5.
  IF sy-subrc <> 0.
MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
        WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
  ENDIF.
**Populating fieldcatalog
  LOOP AT nametab .
    ls_alv_cat-fieldname     = nametab-fieldname .
    ls_alv_cat-ref_table     = tabname.
    ls_alv_cat-ref_field     = nametab-fieldname .
    APPEND ls_alv_cat TO lt_alv_cat.
  ENDLOOP.
**Method for getting the reference for the structure
  CALL METHOD cl_alv_table_create=>create_dynamic_table
      EXPORTING it_fieldcatalog = lt_alv_cat
      IMPORTING ep_table = dref.
**Passing the reference of the structure to field-symbol of type table
  ASSIGN dref->* TO <i_temp>.
  REFRESH i_field.
**Getting detailed structure of table
  CALL FUNCTION 'CRS_GET_DDIC_TABLE'
       EXPORTING
            i_tabname           = tabname
       TABLES
            to_nametab          = i_field
       EXCEPTIONS
            internal_error      = 1
            table_has_no_fields = 2
            table_not_active    = 3
            no_texts_found      = 4
            OTHERS              = 5.
  IF sy-subrc <> 0.
MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
        WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
  ENDIF.
Once you have done this... remember that the program does not know which table is this... but once you have got the table name you can either get the data from the database or if its a structure then you can fill it on your own
  SELECT *
         FROM (tabname)
         INTO CORRESPONDING FIELDS OF TABLE <i_temp>.
  IF sy-subrc NE 0.
  ENDIF.
  SORT : i_begru,
         i_matnr.
**Selecting records,extracted from Class table that meet selection
**creiteria
  LOOP AT <i_temp> ASSIGNING <wa_temp>.
**Assigning BEGRU field
    ASSIGN COMPONENT pos_begru OF STRUCTURE <wa_temp> TO <fs_begru>.
or if you know what could be the structure that might get used
FIELD-SYMBOLS : <fs_bapi_mara>   TYPE bapi_mara,
                 <fs_bapi_marax>  TYPE bapi_marax,
                 <fs_bapi_marc>   TYPE bapi_marc,
                 <fs_bapi_marcx>  TYPE bapi_marcx,
                 <fs_bapi_mpop>   TYPE bapi_mpop,
DATA : dref TYPE REF TO data.
declare like this and then
**BAPI_MARA
  CREATE DATA dref TYPE bapi_mara.
  ASSIGN dref->* TO <fs_bapi_mara>.
**BAPI_MARAX
  CREATE DATA dref TYPE bapi_marax.
  ASSIGN dref->* TO <fs_bapi_marax>.
**BAPI_MARC
  CREATE DATA dref TYPE bapi_marc.
  ASSIGN dref->* TO <fs_bapi_marc>.
Go on creating the required structures on the selection criteria match ... when case
Regards,
Shekhar Kulkarni