PHP继承，子类中重写方法，类之间传递数值

PHP继承：

class Person {
  public $name;
  public $age;

  function __construct($name, $age) {
    $this->name = $name;
    $this->age = $age;
  }

  function describe() {
    return $this->name . ", " . $this->age . " years old.";
  }
}

class Student extends Person {
  public $school;

  function __construct($name, $age, $school) {
    parent::__construct($name, $age);
    $this->school = $school;
  }

  function describe() {
    return parent::describe() . " Attends " . $this->school . ".";
  }
}

$student1 = new Student("Tom", 20, "ABC University");
echo $student1->describe();

子类中重写方法：

class Person {
  public $name;
  public $age;

  function __construct($name, $age) {
    $this->name = $name;
    $this->age = $age;
  }

  function describe() {
    return $this->name . ", " . $this->age . " years old.";
  }
}

class Student extends Person {
  public $school;

  function __construct($name, $age, $school) {
    parent::__construct($name, $age);
    $this->school = $school;
  }

  function describe() {
    return "Student: " . $this->name . ", " . $this->age . " years old. Attends " . $this->school . ".";
  }
}

$student1 = new Student("Tom", 20, "ABC University");
echo $student1->describe();

类之间传递数值：

class Person {
  public $name;
  public $age;

  function __construct($name, $age) {
    $this->name = $name;
    $this->age = $age;
  }
}

class Student {
  public $person;

  function __construct($person) {
    $this->person = $person;
  }

  function describe() {
    return $this->person->name . ", " . $