要在SAP GUI 和 WEB GUI 实现不同功能时，就需要判断是否程序运行环境，可以用以下几种方法判断。
方法一：
DATA: w_username(20)   TYPE c.

  CALL FUNCTION 'GUI_GET_DESKTOP_INFO'
    EXPORTING
      type   = 5
    CHANGING
      return = w_username.

if w_username is initial.
*   running in HTML
else.
*   running in SAP GUI
endif.
方法二：
CALL METHOD CL_GUI_FRONTEND_SERVICES=>GET_COMPUTER_NAME
    CHANGING
      COMPUTER_NAME = V_PCNAM.

  IF V_PCNAM IS INITIAL.
*    html 
  ELSE.
*    sap gui
  ENDIF.
方法三：
DATA : ISWEBGUI TYPE C.
CLEAR ISWEBGUI.
CALL FUNCTION 'GUI_HAS_OBJECTS'
* EXPORTING
* OBJECT_MODEL =
IMPORTING
RETURN = ISWEBGUI
* EXCEPTIONS
*   INVALID_OBJECT_MODEL = 1
*   OTHERS = 2
.
IF ISWEBGUI = 'X'.
" SAP GuI
ELSE.
" WEB GuI
ENDIF.