Here is my proposition based on json_encode() solution with :
If word not found, it still returns 0 equal to false.
function in_array_count($needle, $haystack, $caseSensitive = true) {
if(!$caseSensitive) {
return substr_count(strtoupper(json_encode($haystack)), strtoupper($needle));
}
return substr_count(json_encode($haystack), $needle);
}
Hope it helps.