php自动加载类示例

本例有三个文件，app.php、Student.class.php 和Teacher.cla.php，两个类文件分别在public 和 libs文件夹，其目录结构如下图：

 

<?php
header("Content-type: text/html; charset=utf-8");
//设置中国时区
date_default_timezone_set('PRC');
//注册函数
spl_autoload_register("func1");
spl_autoload_register("func2");
// __autoload("func2");
// require("./public/Student.class.php");
function func1($className)
{
    $filename = "./public/$className.class.php";
    if (file_exists($filename)) require_once($filename);
}
function func2($className)
{
    $filename = "./libs/$className.cla.php";
    if (file_exists($filename)) require_once($filename);
}


$obj1 = new Student();
$obj2 = new Teacher();

Student.class.php位于Teacher文件夹，内容如下：

<?php
class Student
{
    private $name = "Tom";
    private $age = 24;
    public function __construct(){
        echo "{$this->name}的年龄是{$this->age}岁。<br>";
    }
}

Teacher.cla.php位于libs文件夹，内容如下：

<?php
class Teacher
{
    private $name = "Mr Liu";
    private $school = "北京科技大学";
    public function __construct(){
        echo "{$this->name}毕业于{$this->school}";
    }
}