ABAP-选择屏幕下拉框函数

REPORT y4_b4_test7.
SELECTION-SCREEN FUNCTION KEY 1.
PARAMETERS:p_tabnam TYPE dd02l-tabname AS LISTBOX VISIBLE LENGTH  35.

AT SELECTION-SCREEN ON VALUE-REQUEST FOR p_tabnam.
  "下拉菜单函数
  PERFORM frm_set_vrm_list.

FORM frm_set_vrm_list.
  DATA:lt_list TYPE vrm_values.

  SELECT ebeln AS key bukrs AS text INTO TABLE lt_list FROM ekko.

  "p_tabnam的值是KEY值
  CALL FUNCTION 'VRM_SET_VALUES'
    EXPORTING
      id     = 'P_TABNAM'
      values = lt_list.

ENDFORM.