015_class.php

<?php

namespace Fatherspace {
    const FLAG = 123;
    class Person
    {
        protected $weight = 60;
        public function say()
        {
            echo "person hello" . PHP_EOL;
        }
    }

    interface Animal
    { // 接口中的方法不能有方法体
        public function eat();
    }
}

namespace MyNamespace {

    const LastName = "Yao";

    class Student extends \Fatherspace\Person implements \Fatherspace\Animal
    {

        const FirstName = "Xiaoming"; // 常量
        public static $name = "laoer";
        public static $age = 20;

        public $data = array();

        public function __construct($name, $age)
        {
            echo "construct" . PHP_EOL;
            $this->name = $name;
            $this->age = $age;
        }

        public function __destruct()
        {
            echo "destruct" . PHP_EOL;
        }

        public function __toString()
        {
            return "name: " . $this->name . ", age: " . $this->age;
        }

        public function __get($property)
        {
            if (array_key_exists($property, $this->data)) {
                return $this->data[$property];
            } else {
                return "no such property $property" . PHP_EOL;
            }
        }

        public function __set($property, $value)
        {
            $this->data[$property] = $value;
        }

        public function say()
        {
            parent::say();
            echo "hello, " . $this->name . PHP_EOL;
        }

        public function __call($method, $arguments)
        {
            echo "no such method $method" . PHP_EOL;
        }

        public function get_weight()
        {
            return $this->weight;
        }

        public static function get_name_age()
        { // 静态方法访问静态属性
            return "name: " . self::$name . ", age: " . self::$age;
        }


        public function eat()
        {
            echo "eat" . PHP_EOL;
        }
    }
}

namespace {
    echo MyNamespace\LastName . PHP_EOL; // 访问其他命名空间的常量, 这种方式只能访问常量和类和接口
    $stu = new MyNamespace\Student("laoer", 20);
    echo $stu . PHP_EOL;
    $stu->say();
    $stu->hobby = "basketball"; // 通过__set 方法新增属性
    echo $stu->hobby . PHP_EOL; // 通过__get 方法获取属性
    echo $stu->weight . PHP_EOL; // protected属性不能在类外部访问
    echo $stu->get_weight() . PHP_EOL; // 通过方法访问
    echo MyNamespace\Student::get_name_age() . PHP_EOL; // 静态方法访问
    $stu->test_method(); // 不存在的方法
    $stu->eat(); // 实现接口中的方法
    echo MyNamespace\Student::FirstName . PHP_EOL; // 访问常量和访问静态方法一样
    echo "xxxxxx" . PHP_EOL;

    use Fatherspace\Person;

    $man1 = new Person();
    $man1->say();
}