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INSTR

Syntax

INSTR ( [I, ] X$, Y$)

Versions: Extended, Disk

Description

Searches for the first occurrence of string Y$ in X$ and returns the position at which the match is found. Optional offset I sets the position for starting the search. I must be in the range 1 to 255. If I>LEN(X) or if X is null or if Y$ cannot be found, INSTR returns O. If Y$ is null, INSTR returns I or 1. X$ and Y$ may be string variables, string expressions or string literals.

Example

10 X$ = "ABCDEB"
20 Y$ = "B"
30 PRINT INSTR(X$, Y$); INSTR(4, X$, Y$)
RUN
2 6
Ok

Note: If I=0 is specified, an "Illegal function call" error will occur.

See Also

  • ASC - Returns a numerical value that is the ASCII code of the first character of the string X$
  • CHR$ - Returns a one-character string whose ASCII code is the specified value
  • HEX$ - Returns a string which represents the hexadecimal value of the decimal argument
  • LEFT$ - Return the leftmost N characters from a string
  • LEN - Returns the number of characters in X$
  • MID$ - Extract a substring from the middle of a string
  • MID$ Assignment - Replace characters within a string variable
  • OCT$ - Returns a string which represents the octal value of the decimal argument
  • RIGHT$ - Return the rightmost N characters from a string
  • SPACE$ - Returns a string of I spaces
  • SPC - Prints I blanks on the terminal
  • STR$ - Convert a number to its string representation
  • [STRING](string_dollar.md) - Returns a string of length I whose characters all have ASCII code J or the first character of X
  • VAL - Returns the numerical value of string X$