添加额外属性 * $result = ArrayHelper::map($array, 'type', 'name', 'id') * * $array = [ * ['id' => '123', 'name' => 'aaa', 'class' => 'x', 'type' => 'type1'], * ['id' => '124', 'name' => 'bbb', 'class' => 'x', 'type' => 'type1'], * ['id' => '345', 'name' => 'ccc', 'class' => 'y', 'type' => 'type2'], * ]; * * // the result is: * // [ * // '123' => [ * // 'type' => 'type1', * // ], * // '124' => [ * // 'type' => 'type1', * // ], * // '345' => [ * // 'type' => 'type2', * // ], * // ] * * @param $array * @param $from * @param $to * @param null $group * @return array */ public static function map($array, $from, $to, $group = null) { $result = []; foreach ($array as $element) { $key = ArrayHelper::getValue($element, $from); $value = ArrayHelper::getValue($element, $to); if ($group !== null) { $result[ArrayHelper::getValue($element, $group)][$key] = $value; } else { $result[$key] = $value; } } return $result; } }