public static function doesArrayContainOnlyStringKeys($arr)
    {
        if (!is_array($arr) || empty($arr)) {
            return false;
        }

        return count(array_filter(array_keys($arr), 'is_string')) == count(array_keys($arr));
    }
public static function doesArrayContainOnlyStringKeys($arr)
    {
        if (!is_array($arr) || empty($arr)) {
            return false;
        }

        return count(array_filter(array_keys($arr), 'is_string')) == count(array_keys($arr));
    }
public static function doesArrayContainOnlyStringKeys ( $ arr ) { if ( ! is_array ( $ arr ) || empty ( $ arr ) ) { return false ; } return count ( array_filter ( array_keys ( $ arr ) , 'is_string' ) ) == count ( array_keys ( $ arr ) ) ; }
Returns true only if given input is an array with all of it's keys of type string.
@param  mixed $arr
@return bool  True if array contains all string keys. Otherwise, false.
Returns true only if given input is an array with all of it s keys of type string .