PHP面向对象笔记 —— 132 延迟绑定复习

// ===代码部分1===

// =延迟绑定= //

class Animal {
    const age = 1;
    public static $leg = 4;

    public static function cry() {
        echo '呜呜
';
    }

    public static function t1() {
        self::cry();
        echo self::age,'
';
        echo self::$leg,'
';
    }

    public static function t2() {
        static::cry();
        echo static::age,'
';
        echo static::$leg,'
';
    }
}

class Human extends Animal {
    const age = 30;
    public static $leg = 2;

    public static function cry() {
        echo '哇哇
';
    }
}

/*
class Stu extends Human {
    const age = 16;
    public static $leg = 3;

    public static function cry() {
        echo '嘤嘤
';
    }
}

Stu::t1(); //呜呜，1，4
Stu::t2(); //嘤嘤，16，3
//static调用cry()方法会移植到自身Stu类来执行
*/

// ===代码部分2===

class Stu extends Human {
    const age = 16;
    //public static $leg = 3;

    public static function cry() {
        echo '嘤嘤
';
    }
}

Stu::t2(); //嘤嘤，16，2
//把Stu中的leg拿掉，会转到父类中找leg，结果leg=2