PHP按字段分组

我有三个班：运输、维修站、目录运输：

$service1=new ServiceStation('Service1','Address1');
$service2=new ServiceStation('Service2','Address2');
$t1=new Transport("t1",'type1',100,'carcase1','engine1','chassis1',$service1);
$t2=new Transport("t2",'type2',200,'carcase2','engine2','chassis2',$service1);
$t3=new Transport("t3",'type3',300,'carcase3','engine3','chassis3',$service2);
$catalog=new CatalogTransport();
$catalog->addTransport($t1);
$catalog->addTransport($t2);
$catalog->addTransport($t3);
$catalog->showCatalog();

我的CatalogTransport类：

class CatalogTransport{
    private $catalog = [];
    public function addTransport(Transport $t) {
        $this->catalog[] = $t;
    }

    public function showCatalog() {
        echo '<pre>';
        print_r($this->catalog);
        echo '</pre>';
    }
}

如何按现场服务对其进行分组

我希望它能够：

服务1：

t1，t2

服务2： t3

---

如何解决我的问题？

添加一些使用数组映射函数对对象数组进行正确排序的方法例如非常简单的方法：首先，您应该为“ServiceStation”对象使用getter方法，因为名称是私有属性。然后您可以迭代$this->catalog并创建一个包含所有“服务”对象的数组。注意复制品。如果Service1或Service2是对象，则应序列化它们。然后再次迭代$this->catalog，与数组进行比较，并根据需要创建hiérarchie。因此，BigO复杂性将是O（2n），因此O（n）。。。可接受的

Array
(
     [0] => Transport Object
    (
        [name:Transport:private] => t1
        [type:Transport:private] => type1
        [weight:Transport:private] => 100
        [carcase:Transport:private] => carcase1
        [engine:Transport:private] => engine1
        [chassis:Transport:private] => chassis1
        [service:Transport:private] => ServiceStation Object
            (
                [name:ServiceStation:private] => Service1
                [address:ServiceStation:private] => Address1
            )

    )

[1] => Transport Object
    (
        [name:Transport:private] => t2
        [type:Transport:private] => type2
        [weight:Transport:private] => 200
        [carcase:Transport:private] => carcase2
        [engine:Transport:private] => engine2
        [chassis:Transport:private] => chassis2
        [service:Transport:private] => ServiceStation Object
            (
                [name:ServiceStation:private] => Service1
                [address:ServiceStation:private] => Address1
            )

    )

[2] => Transport Object
    (
        [name:Transport:private] => t3
        [type:Transport:private] => type3
        [weight:Transport:private] => 300
        [carcase:Transport:private] => carcase3
        [engine:Transport:private] => engine3
        [chassis:Transport:private] => chassis3
        [service:Transport:private] => ServiceStation Object
            (
                [name:ServiceStation:private] => Service2
                [address:ServiceStation:private] => Address2
            )

    )

)