ALV

呼叫ALV之前，要先定義Layout和Fieldcat
TYPE-POOLS: slis.

DATA: fieldcat TYPE slis_t_fieldcat_alv WITH HEADER LINE,
            layout TYPE slis_layout_alv,
            w_repid LIKE sy-repid.

相關函數：    
REUSE_ALV_FIELDCATAOG_MERGE: Create field catalog from dictionary structure or internal table. (或者自定義欄位名稱)
REUSE_ALV_GRID_DISPLAY: Output of a simple list (single-line).
REUSE_ALV_LIST_DISPLAY: Output a simple list (single line or several lines).