function

line_index 行号

line_index( flight_tab[ KEY cities
                                cityfrom = 'FRANKFURT'
                                cityto   ='NEWYORK'  ] )

lines 行数

lines( it_tab )

sy-abcde

就是英语的字符  

strlen

strlen( ) 长度

cmax | cmin

    从左到右选择最大值最小值

cmin( val1 = itab[ 1 ]
val2 = itab[ 2 ]
val3 = itab[ 3 ]
val4 = itab[ 4 ]).

concat_lines_of

"sep 是分隔符  
DATA(itab) = VALUE itab( ( 'ABAP' ) ( 'Objects' ) ).
cl_demo_output=>display(
  concat_lines_of( table = itab sep = ` ` ) ).

insert

"result = X X X X X
DATA(result) = `XXXXX`. 
result = 
REDUCE #( INIT r = result 
        FOR j = 1 UNTIL j > strlen( result ) - 1 
        NEXT r = insert( val = r sub = ` ` off = j * 2 - 1 ) ). 

match

"返回 x2 但是搞不懂为什么  occ = 2 表示第二次出现的时候
cl_demo_output=>display(        “ . 可以匹配除了换行符（\n）以外的任意一个字符
match( val = 'x1 x2 x3' regex = 'x.' occ = 2 ) ).

repeat

”result =  '111111111'
DATA(result) = repeat( val = ` ` occ = 10 ).

replace

" 比较复杂的正则表达式
DATA(html) = `<title>This is the <i>Title</i></title>`. 
DATA(repl)   = `i`. 
html = replace( val   = html 
                regex = repl && `(?![^<>]*>)` 
                with  = `<b>$0</b>` 
                occ   =   0 ). 

reverse 反转函数

 DATA(result) = reverse( sy-abcde ). “结果是从z 到 a 

segment 没有弄懂

DATA  result TYPE string. 

DO. 
  TRY. 
      result = segment( val   = 'AB\brCD\brEF\brGH' 
                        index = sy-index 
                        sep = `\br` ). 
      ... 
    CATCH cx_sy_strg_par_val. 
      EXIT. 
  ENDTRY. 
ENDDO. 

DO. 
  TRY. 
      result = segment( val   = 'AB  CD - EF_GH' 
                        index = sy-index 
                        space = ` -_` ). 
      ... 
    CATCH cx_sy_strg_par_val. 
      EXIT. 
  ENDTRY. 
ENDDO. 

shfit_left shfit_right

见代码 DEMO_SHIFT_SUBSTRING “ 字符位移 大量 新语法的使用

SUBSTRING

result = substring( val = 'ABCDEFGH' off = 2 len = 2 )."CD

result = substring_from( val = 'ABCDEFGH' sub
 = 'CD' )."CDEFGH

result = substring_after( val = 'ABCDEFGH' sub = 'CD' )."EFGH

result = substring_before( val = 'ABCDEFGH' sub = 'CD' )."AB

result = substring_to( val = 'ABCDEFGH' sub = 'CD' )."ABCD

TO_UPPER TO_LOWER TO_MIXED FORM_MIXED 字符的大小变化

DEMO_TO_FROM_MIXED