ABAP中获得内表字段名

REPORT  ZCYH_FIELDNAMEGET.
types:
  begin of typ_itab,
  a type c,
  b type c,
  c type c,
  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.
* FIELD-SYMBOLS:
*                 <fs_comp_wa> TYPE abap_compdescr.
         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 ASSIGNING <fs_comp_wa>.

*  WRITE: / <fs_comp_wa>-NAME.
  LOOP AT l_descr_ref->components INTO WA_TABLE .
  WRITE :/ WA_TABLE-NAME.

  ENDLOOP.

                                                          ----------------------------Alar Cheng