abap动态内表获取字段名

REPORT  ztest0003 NO STANDARD PAGE HEADING.

START-OF-SELECTION.

  TYPES:
    BEGIN OF typ_itab,
    aaa(20) TYPE c,
    bbb TYPE i,
    ccc TYPE p LENGTH 12 DECIMALS 3,
    END OF typ_itab.
  DATA i_itab TYPE TABLE OF typ_itab.
  DATA:
          l_tabledescr_ref TYPE REF TO cl_abap_tabledescr,
          l_descr_ref      TYPE REF TO cl_abap_structdescr.

  DATA wa_table TYPE abap_compdescr.

  l_tabledescr_ref ?= cl_abap_typedescr=>describe_by_data( i_itab ).
  l_descr_ref ?= l_tabledescr_ref->get_table_line_type( ).

  LOOP AT l_descr_ref->components INTO wa_table .
    WRITE :/ wa_table-name
      ,wa_table-type_kind
      ,wa_table-length
      ,wa_table-decimals
      .
  ENDLOOP.