INDEX function

Returns an INTEGER value that indicates the position of the target string within the source string.


INDEX ( `source` , `target` [ , `starting` ] )

A CHARACTER or LONGCHAR expression whose position you want to locate in source. If target does not exist within source, INDEX returns a 0.

For this example, you must enter 1, 2, 3, 4, or 5. The INDEX function checks if the digit exists in the string "12345".

r-index.p
DEFINE VARIABLE x AS CHARACTER NO-UNDO FORMAT "9" LABEL "Enter a digit between 1 and 5". DEFINE VARIABLE show AS CHARACTER NO-UNDO FORMAT "x(5)" EXTENT 5 LABEL "Literal" INITIAL ["One", "Two", "Three", "Four", "Five"]. REPEAT: SET x AUTO-RETURN. IF INDEX("12345",x) = 0 THEN DO: MESSAGE "Digit must be 1,2,3,4, or 5. Try again.". UNDO, RETRY. END. ELSE DISPLAY show[INTEGER(x)]. END.

r-index.p

DEFINE VARIABLE x    AS CHARACTER NO-UNDO FORMAT "9" 
  LABEL "Enter a digit between 1 and 5". 
DEFINE VARIABLE show AS CHARACTER NO-UNDO FORMAT "x(5)" EXTENT 5  
  LABEL "Literal" INITIAL ["One", "Two", "Three", "Four", "Five"]. 
REPEAT: 
  SET x AUTO-RETURN. 
  IF INDEX("12345",x) = 0 THEN DO: 
    MESSAGE "Digit must be 1,2,3,4, or 5. Try again.". 
    UNDO, RETRY. 
  END. 
  ELSE DISPLAY show[INTEGER(x)]. 
END.

r-index2.p
DEFINE VARIABLE positions AS CHARACTER NO-UNDO FORMAT "x(60)". DEFINE VARIABLE sentence AS CHARACTER NO-UNDO FORMAT "x(72)". DEFINE VARIABLE vowel AS CHARACTER NO-UNDO FORMAT "x". DEFINE VARIABLE found AS INTEGER NO-UNDO. DEFINE VARIABLE loop AS INTEGER NO-UNDO. DEFINE VARIABLE start AS INTEGER NO-UNDO. FORM sentence LABEL "Type in a sentence" WITH FRAME top TITLE "This program will tell where the vowels are in a sentence.". SET sentence WITH FRAME top. DO loop = 1 TO 5: ASSIGN positions = "" vowel = SUBSTRING("aeiou",loop,1) start = 1 found = INDEX(sentence,vowel,start). DO WHILE found > 0: ASSIGN positions = positions + STRING(found) + " " start = found + 1 found = INDEX(sentence,vowel,start). END. DISPLAY vowel LABEL "Vowel" positions LABEL "Is found at locations..." WITH 5 DOWN. DOWN. END.

r-index2.p

DEFINE VARIABLE positions AS CHARACTER NO-UNDO FORMAT "x(60)". 
DEFINE VARIABLE sentence  AS CHARACTER NO-UNDO FORMAT "x(72)". 
DEFINE VARIABLE vowel     AS CHARACTER NO-UNDO FORMAT "x". 
DEFINE VARIABLE found     AS INTEGER   NO-UNDO. 
DEFINE VARIABLE loop      AS INTEGER   NO-UNDO. 
DEFINE VARIABLE start     AS INTEGER   NO-UNDO. 
FORM sentence LABEL "Type in a sentence" 
  WITH FRAME top 
  TITLE "This program will tell where the vowels are in a sentence.". 
SET sentence WITH FRAME top. 
DO loop = 1 TO 5: 
  ASSIGN 
    positions = "" 
    vowel     = SUBSTRING("aeiou",loop,1) 
    start     = 1 
    found     = INDEX(sentence,vowel,start). 
  DO WHILE found > 0: 
    ASSIGN 
      positions = positions + STRING(found) + " " 
      start     = found + 1 
      found     = INDEX(sentence,vowel,start). 
  END. 
  DISPLAY vowel LABEL "Vowel" positions LABEL "Is found at locations..."  
    WITH 5 DOWN. 
  DOWN. 
END.

If either operand is case sensitive, then the search is case sensitive.

If the target string is null, the result is 0.

The INDEX function is double-byte enabled. You can specify target and source strings for the INDEX function that contain double-byte characters.