SAP ABAP 新语法补充（DATA、COND、SWITCH、VALUE、FOR、REDUCE、CONV、CORRESPONDING、GROUP BY、FELTER）

新语法	示例	等价于/说明
DATA	（1）DATA(TEXT) = ‘ABCDE’. （2）LOOP AT ITAB INTO DATA(WA).          ……      ENDLOOP.	（1）DATA TEXT TYPE STRING. TEXT = ‘ABCDE’. （2）DATA WA LIKE LINE OF ITAB. LOOP AT ITAB INTO WA. …… ENDLOOP.
COND	LV_STR = COND #(WHEN LV_STR IS INITIAL THEN ‘ABCDE’ ELSE LV_STR).	IF LV_STR IS INITIAL.        LV_STR = ‘ABCDE’. ELSE.        LV_STR = ‘ ‘. ENDIF.
SWITCH	LV_STR = SWITCH #( N WHEN 1 THEN ‘ABCDE‘ WHEN 2 THEN ‘FGHTL).	CASE N.    WHEN 1.       LV_STR = ‘ABCDE’.    WHEN 2.       LV_STR = ‘FGHTL’.    WHEN OTHERS.       LV_STR = ‘ ‘. ENDCASE.
VALUE	ITAB= VALUE #( ( ID = 1 NAME = ‘LILI’)                (ID = 2 NAME = ‘LIMI)).	TYPES:BEGIN OF TY_ITAB,         ID TYPE I,         NAME TYPE STRING,        END OF TY_ITAB. DATA:ITAB TYPE TABLE OF TY_ITAB. 再赋值
FOR	DATA(ITAB2) = VALUE ITAB2(FOR WA IN ITAB1 WHERE ( ID  < 50 ) ( ID = WA-ID NAME = WA-NAME AGE = WA-AGE )).	加强版的LOOP AT，可用于填充内表、根据条件汇总、计算等操作
REDUCE	DATA( SUM ) = REDUCE I( INIT X = 0 FOR WA IN ITAB NEXT X = X+WA-AGE ).	可用于汇总计算
CONV	LV_STR = ‘001024.012’. LV_INT = CONV I( LV_STR ).	数据类型转换，不需要中间变量
CORRESPONDING	STRUCT2 = CORRESPONDING #( STRUCT1 ).	用于实现结构和内表之间的动态赋值操作
GROUP BY	LOOP AT ITAB ASSIGNING FIELD-SYMBOL(<FS_ITAB>) GROUP BY <FS_ITAB>-ID.	相当于SQL中的GROUP BY，用于内表处理
FELTER	DATA( ITAB1 ) = FILTER #( ITAB USING KEY ID)单值过滤 DATA( ITAB2 ) = FILTER #( ITAB USING KEY ID WHERE AGE = CONV #( TO_UPPER( AGE )))多值过滤	过滤，可以指定一个或多个值进行过滤