在前面的博文中，已经讲了封装的思路和实现，主要是利用 cl_salv_data_descr=>read_structdescr () 方法来实现。在这里，贴出代码方便大家参考。

编写获取内表组件的通用方法

form frm_get_fields using    pt_data type any table
                    changing pt_fields type ddfields.

  data: lr_tabdescr type ref to cl_abap_structdescr,
        lr_data     type ref to data,
        lt_fields   type ddfields.

  create data lr_data like line of pt_data.

  lr_tabdescr ?= cl_abap_structdescr=>describe_by_data_ref( lr_data ).
  lt_fields    = cl_salv_data_descr=>read_structdescr( lr_tabdescr ).

  pt_fields = lt_fields.
endform.   

编写函数获取FieldCatalog

function z_falv_field_catalog.
*"----------------------------------------------------------------------
*"*"Local Interface:
*"  IMPORTING
*"     REFERENCE(IT_OUTPUT) TYPE  ANY TABLE
*"  TABLES
*"      FIELD_CATALOG TYPE  SLIS_T_FIELDCAT_ALV
*"----------------------------------------------------------------------

  data: lt_ddfields type ddfields,
        ls_fields   type dfies.
  data: ls_fieldcat type slis_fieldcat_alv.
  data: lt_fieldcat type slis_t_fieldcat_alv.

  perform frm_get_fields using it_output[] changing lt_ddfields[].

  loop at lt_ddfields into ls_fields.
    move-corresponding ls_fields to ls_fieldcat.
    append ls_fieldcat to lt_fieldcat.
    clear ls_fieldcat.
  endloop.

  append lines of lt_fieldcat to field_catalog.

endfunction.