mb_stristr()

mb_stristr() — Finds first occurrence of a string within another, case insensitive.

Built-in function of PHP 8.5. The manual lists it as available in PHP 5 >= 5.2.0, PHP 7, PHP 8. This page is the reference card: signature, parameters and return value, plus the changelog and the example the manual provides.

What it does

mb_stristr() finds the first occurrence of needle in haystack and returns the portion of haystack. Unlike mb_strstr(), mb_stristr() is case-insensitive. If needle is not found, it returns false.

Signature

mb_stristr(string $haystack, string $needle, bool $before_needle = false, ?string $encoding = null): string|false

Parameters

Parameter	Type	What it takes
$haystack	string	The string from which to get the first occurrence of needle
$needle	string	The string to find in haystack
$before_needle	bool	Determines which portion of haystack this function returns. If set to true, it returns all of haystack from the beginning to the first occurrence of needle (excluding needle). If set to false, it returns all of haystack from the first occurrence of needle to the end (including needle).
$encoding	?string	The encoding parameter is the character encoding. If it is omitted or null, the internal character encoding value will be used.

Return value

Returns the portion of haystack, or false if needle is not found.

Example

The PHP manual ships no example for mb_stristr(); the signature and the parameter table above are the contract.

Changelog

Version	Change
8.0.0	needle now accepts an empty string.
8.0.0	encoding is nullable now.
8.0.0	Now throws a ValueError if encoding is an invalid encoding. Previously, an E_WARNING was emitted and false was returned.