Checking if a string contains a substring is very frequently occuring use case in PHP code. PHP functions strpos or stripos (case insensitive version) can be used for this. Here are some examples.
strpos example
<?php
$str = "Hello world";
$pos = strpos($str, "world");
if ($pos !== FALSE) {
echo "FOUND at post:$pos\n";
} else {
echo "NOT_FOUND\n";
}
?>FOUND at post:6
Env: PHP 8.2.29 (Linux)
stripos example
<?php
$str = "Hello world";
$pos = strpos($str, "WORLD");
if ($pos !== FALSE) {
echo "strpos: FOUND at post:$pos\n";
} else {
echo "strpos: NOT_FOUND\n";
}
$pos = stripos($str, "WORLD");
if ($pos !== FALSE) {
echo "stripos: FOUND at post:$pos\n";
} else {
echo "stripos: NOT_FOUND\n";
}
?>strpos: NOT_FOUND stripos: FOUND at post:6
Env: PHP 8.2.29 (Linux)