如何在类的方法中引用include进来的文件中的变量？

Question

include 'db_link.php'; class Search{ private $S_id; private $D_id; private $range; public function setS_id($S_id){ $this->S_id = $S_id; } public function get_Sid(){ return $this->S_id; } public function setD_id($D_id){ $this->D_id = $D_id; } public function getD_id(){ return $this->D_id; } public function checkPerson($S_name){ } 在方法checkPerson（）中如何访问'db_link.php'的变量？

Answer 1

我都是这样的：

class A{
    public $db;
    public function __construct(){
        include 'db_link.php';
        $this->db = $arg_from_db_link;
    }
}

Answer 2

a.php

$a = 111;
return $a;

b.php

$c = include 'a.php';
echo $c;