PHP类与对象

//创建一个类
class Student
{
   //定义成员属性用public声明,public指的是共用的，任何地方都能访问
   //姓名
   public $name = 'lemon';//设置初始值
   //学号
   public $no;
   //成绩
   public $score;

   //成员方法
   public function sing($songName){
      echo "学生会唱{$songName}歌";
   }

   public function run(){
      echo "学生去跑步了";
   }

   public function showSelf(){
      echo "我叫".$this->name.",我的学号是{$this->no},我的成绩是{$this->score}";
      $this->sing("成都");
   }
}

class Teacher{
   public $name;
   public $no;
   public $course;

   public function teachBook(){
      echo "老师会教书";
   }

   public function dance(){
      echo "老师会跳舞";
   }
}

//实例化对象
$student1 = new Student();
echo $student1->name;
$student1->name = '柠檬';
echo $student1->name;
$student1->sing("国");
echo"<hr>";
$student2 = new Student();
$student2->name = "张三";
$student2->no = "1001";
$student2->score = "100";
$student2->showSelf();

include "";//用来引用class类,出现错误会警告
require "";//用来引用class类，出现错误会崩溃
include_once "";//只引用一次，多次引用不会报错
require_once "";//只引用一次，多次引用不会报错