src/Guzzle/Common/Collection.php
public function keySearch($key)
    {
        foreach (array_keys($this->data) as $k) {
            if (!strcasecmp($k, $key)) {
                return $k;
            }
        }

        return false;
    }
public function keySearch($key)
    {
        foreach (array_keys($this->data) as $k) {
            if (!strcasecmp($k, $key)) {
                return $k;
            }
        }

        return false;
    }
public function keySearch ( $ key ) { foreach ( array_keys ( $ this -> data ) as $ k ) { if ( ! strcasecmp ( $ k , $ key ) ) { return $ k ; } } return false ; }
Case insensitive search the keys in the collection

@param string $key Key to search for

@return bool|string Returns false if not found, otherwise returns the key
Case insensitive search the keys in the collection