我知道我在这方面非常晚，但我提出了一个相当灵活的模式，应该允许一些真正有趣和通用的实现。

像往常一样设置类，使用您喜欢的任何变量。

class MyClass{ protected $myVar1; protected $myVar2; public function __construct($obj = null){ if($obj){ foreach (((object)$obj) as $key => $value) { if(isset($value) && in_array($key, array_keys(get_object_vars($this)))){ $this->$key = $value; } } } } } When you make your object just pass an associative array with the keys of the array the same as the names of your vars, like so... $sample_variable = new MyClass([ 'myVar2'=>123, 'i_dont_want_this_one'=> 'This won\'t make it into the class' ]); print_r($sample_variable); The print_r($sample_variable); after this instantiation yields the following: MyClass Object ( [myVar1:protected] => [myVar2:protected] => 123 ) Because we've initialize $group to null in our __construct(...), it is also valid to pass nothing whatsoever into the constructor as well, like so... $sample_variable = new MyClass(); print_r($sample_variable); Now the output is exactly as expected: MyClass Object ( [myVar1:protected] => [myVar2:protected] => ) The reason I wrote this was so that I could directly pass the output of json_decode(...) to my constructor, and not worry about it too much. This was executed in PHP 7.1. Enjoy!

PHP是一种动态语言，因此不能重载方法。你必须像这样检查参数的类型:

class Student 
{
   protected $id;
   protected $name;
   // etc.

   public function __construct($idOrRow){
    if(is_int($idOrRow))
    {
        $this->id = $idOrRow;
        // other members are still uninitialized
    }
    else if(is_array($idOrRow))
    {
       $this->id = $idOrRow->id;
       $this->name = $idOrRow->name;
       // etc.  
    }
}

public function __construct() {
    $parameters = func_get_args();
    ...
}

$o = new MyClass('One', 'Two', 3);

现在$ parameters将是一个值为'One'， 'Two'， 3的数组。

编辑,

我可以加上

func_num_args()

会给出函数的参数个数。

嗯，很惊讶我还没有看到这个答案，假设我要参加竞选。

class Action {
    const cancelable    =   0;
    const target        =   1
    const type          =   2;

    public $cancelable;
    public $target;
    public $type;


    __construct( $opt = [] ){

        $this->cancelable   = isset($opt[cancelable]) ? $opt[cancelable] : true;
        $this->target       = isset($opt[target]) ?     $opt[target] : NULL;
        $this->type         = isset($opt[type]) ?       $opt[type] : 'action';

    }
}


$myAction = new Action( [
    Action::cancelable => false,
    Action::type => 'spin',
    .
    .
    .
]);

您可以选择将这些选项分离到它们自己的类中，例如扩展脾。

abstract class ActionOpt extends SplEnum{
    const cancelable    =   0;
    const target        =   1
    const type          =   2;
}

更现代的方法: 你把独立的类混合成一个，实体和数据水合。 对于你的案例，你应该有两个类:

class Student 
{
   protected $id;
   protected $name;
   // etc.
}
class StudentHydrator
{
   public function hydrate(Student $student, array $data){
      $student->setId($data['id']);
      if(isset($data['name')){
        $student->setName($data['name']);
      }
      // etc. Can be replaced with foreach
      return $student;
   }
}

//usage
$hydrator = new StudentHydrator();
$student = $hydrator->hydrate(new Student(), ['id'=>4]);
$student2 = $hydrator->hydrate(new Student(), $rowFromDB);

另外请注意，您应该使用doctrine或其他已经提供自动实体水合的ORM。 你应该使用依赖注入来跳过手动创建像StudentHydrator这样的对象。

另一种选择是像这样在构造函数中使用默认参数

class Student {

    private $id;
    private $name;
    //...

    public function __construct($id, $row=array()) {
        $this->id = $id;
        foreach($row as $key => $value) $this->$key = $value;
    }
}

这意味着你需要实例化一行像这样:$student = new student ($row['id']， $row)，但保持你的构造函数漂亮和干净。

另一方面，如果你想利用多态性，那么你可以创建两个类，像这样:

class Student {

    public function __construct($row) {
         foreach($row as $key => $value) $this->$key = $value;
    }
}

class EmptyStudent extends Student {

    public function __construct($id) {
        parent::__construct(array('id' => $id));
    }
}