int array_search(array $arrayname, string $value[, int $flags])

Checks to see if $value (a string) is in the array $arrayname

Returns the first index into the array that equals $value or returns -1 if $value is not found in the array

$flags (optional)

1 - case-sensitive search (else performs a case-insensitive search)

This function is supported only in CSE HTML Validator v12.0030 and later.