文件包括的本质与作用域,实例演示&演示关键字

<?php
// 1. 文件包括的本质与作用域,实例演示;
include __DIR__ . "/static/p1.php";
echo $username . "<hr>";
require __DIR__ . "/static/p1.php";
echo $username . "<hr>";
echo "Hello " . include __DIR__ . "/static/p1.php";
echo "<br/>";

p1

<?php
$username = "Dave";
return "php.cn";

<?php
// 2. 将课堂上讲到的所有关键字,全部实例演示一遍
// class/new/extends/public/private/protected/interface/abstruct...
//final
final class numberPhp{
    private $Pi = 3.1415926;
    public function getPi(){
        return $this->Pi;
    }
}
$np = new numberPhp;
echo $np->getPi();
echo "<hr>";
//class / new
//public,private,protected
class phpcn{
    const ClassVersion = "19";
    private $course;
    protected $student;
    public $coursePlan;
    public static $teacher="猪老师";
    public function __construct(string $course, string $student,string $coursePlan){
        $this->course = $course;
        $this->student = $student;
        $this->coursePlan = $coursePlan;
    }
    public function getInfo(){
        return $this->course . "include " . $this->student . " .And crouse plan " . $this->coursePlan;
    }
    public static function getTeacher(){
        return self::$teacher;
    }
}
$CClass = new phpcn("php ","Dave, John", "js,php.");
echo $CClass->getInfo();
echo "<hr>";
echo phpcn::getTeacher();
echo "<hr>";
// extends
class Dave extends phpcn{
    private $age = 20;
    public function getInfo(){
        return parent::getInfo()." .Also, Dave age is " . $this->age;
    }
}
$dave1 = new Dave("php ","Dave, John", "js,php.");
echo $dave1->getInfo();
echo "<hr>";
// abstract
abstract class Person{
    abstract public function age();
}
class mingming extends Person{
    private $age = 10;
    public function age(){
        return $this->age;
    }
}
$mm = new mingming;
echo $mm->age();
echo "<hr>";
// interface,implements
interface human{
    public function eat();
}
class xiaowang implements human{
    private $obj = "汉堡";
    public function eat(){
        return "喜欢吃" . $this->obj;
    }
}
$xw = new xiaowang;
echo $xw->eat();
echo "<hr>";