PHP Manual: mb_substr

function mb_substr_count(string $haystack, string $needle, ?string $encoding = null): int

Counts the number of times the needle substring occurs in the haystack string.

haystack: The string being checked.
needle: The string being found.
encoding: The encoding parameter is the character encoding. If it is omitted or null, the internal character encoding value will be used.

The number of times the needle substring occurs in the haystack string.

As of PHP 8.0.0, a ValueError is thrown if encoding is an invalid encoding. Prior to PHP 8.0.0, an E_WARNING was emitted instead.

Version	Description
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.

Example #1 mb_substr_count() example

<?php
echo mb_substr_count("This is a test", "is"); // prints out 2
?>

mb_substr_count