abap 三种替换字符串中首字母的三种方法

"替换字符串中的某一个字符
DATA:lv_char TYPE  c VALUE 'C01' LENGTH 10.
lv_char+0(1) = 'B'.
WRITE:lv_char.
OVERLAY lv_char WITH 'B' ONLY lv_char.
WRITE: / lv_char.
REPLACE FIRST  OCCURRENCE OF 'C' IN LV_CHAR WITH 'B'.
WRITE: / lv_char.

此三种方法均能将C01转变成B01.

此处的类型是char如果是字符串则不能用第一种方法
要用replace来实现

DATA:lv_str TYPE string VALUE 'D01'.
REPLACE SECTION OFFSET 0 LENGTH 1  OF LV_STR WITH 'B'.
WRITE:/ lv_str.