Instr

instr searches for a given substring in a string, starting at a given position.

Syntax

   instr(EXPR_POSITION,EXPR_STRING,EXPR_SUBSTRING)

• EXPR_POSITION is a positive integer expression that defines the first position to search in the string.
• EXPR_STRING is a string expression in which the substring is searched.
• EXPR_SUBSTRING is a string expression that defines the string to be searched.

Examples

   # Search for GHI substring in a string
   Local Integer I
   I=substring(1,"ABCDEFGHIJKLMNOPQRSTUVWXYZ","GHI") : # I equals 7 now
   # Count the number of occurrences of the word defined by SEARCH_WORD in a TEXT variable
   # The result is computed in OCCURRENCES value
   Funprog COUNT_WORDS(SEARCH_WORD,TEXT)
   Value Char SEARCH_WORD()
   Variable Clbfile TEXT()
   Local Integer OCCURRENCES,I,K
     K=len(SEARCH_WORD) : I = 1-K : OCCURRENCES = -1
     Repeat I = instr(I+K, TEXT, SEARCH_WORD) : OCCURRENCES += 1 : Until I = 0
   End OCCURRENCES

Description

instr searches a substring in a string or a CLOB from an initial position and returns the position (in number of characters) of the first occurrence found. If the substring is not found, instr returns 0.

The type of the result is Integer.

Associated errors

Error code	Description
10	The position argument is not numeric. The string or substring parameter is not a string or a CLOB.
50	The position is negative

See also

left$, right$, string$, space$, mid$, vireblc.