string - 在 COBOL 中查找子字符串的索引

Question

我正在寻找字符串中出现指定子字符串的位置。

例如，在字符串“green eggs and ham”中查找子字符串“green”应该返回 1，但从“green eggs and green ham”中查找子字符串会返回 1 和 14。

我应该怎么做？

编辑 1:更改措辞，使位置从 1 开始，而不是 0。 编辑 2:我可以在以下代码段中找到作为 WS-POINTER 的第一个实例:

 MOVE 1 TO  WS-POINTER

 UNSTRING WS-STRING(1:WS-STRING-LEN)
  DELIMITED BY LT-MY-DELIMITER
  INTO WS-STRING-GARBAGE                             
  WITH POINTER WS-POINTER
 END-UNSTRING                   

Answer 1

AFAIK COBOL 没有在字符串中查找字符串位置的语句，因此需要手动完成。但是，COBOL 确实有一条语句可以计算字符串中字符串的出现次数: INSPECT string TALLYING counter FOR ALL 搜索字符串

这是一个在 OpenCOBOL 中运行的示例程序(请参阅 OpenCobol.org):

   IDENTIFICATION DIVISION.
   PROGRAM-ID. OCCURRENCES.

   ENVIRONMENT DIVISION.
   INPUT-OUTPUT SECTION.
   FILE-CONTROL.

   DATA DIVISION.
   FILE SECTION.

   WORKING-STORAGE SECTION.
   01  TEST-STRING-1                    PIC X(30)
       VALUE 'green eggs and ham'.
   01  TEST-STRING-2                    PIC X(30)
       VALUE 'green eggs and green ham'.
   01  TEST-STRING                      PIC X(30).
   01  SEARCH-STRING                    PIC X(05)
       VALUE 'green'.
   01  MATCH-COUNT                      PIC 9.
   01  SEARCH-INDEX                     PIC 99.
   01  MATCH-POSITIONS.
       05  MATCH-POS                    PIC 99 OCCURS 9 TIMES.

   PROCEDURE DIVISION.
   MAIN.
       MOVE TEST-STRING-1 TO TEST-STRING
       PERFORM FIND-MATCHES

       MOVE TEST-STRING-2 TO TEST-STRING
       PERFORM FIND-MATCHES

       STOP RUN
       .

   FIND-MATCHES.
       MOVE ZERO TO MATCH-COUNT 
       INSPECT TEST-STRING TALLYING MATCH-COUNT
           FOR ALL SEARCH-STRING.
       DISPLAY 'FOUND ' MATCH-COUNT ' OCCURRENCE(S) OF '
           SEARCH-STRING ' IN:'
       DISPLAY TEST-STRING
       DISPLAY 'MATCHES FOUND AT POSITIONS: ' WITH NO ADVANCING
       PERFORM VARYING SEARCH-INDEX FROM 1 BY 1
           UNTIL SEARCH-INDEX = 30
           IF TEST-STRING (SEARCH-INDEX:5) = SEARCH-STRING
               DISPLAY SEARCH-INDEX ' ' WITH NO ADVANCING
       END-PERFORM
       DISPLAY ' '
       DISPLAY ' '
       .