register_shutdown_function(array(‘Debug’,'fatalError’)); //定义PHP程序执行完成后执行的函数
set_error_handler(array(‘Debug’,'appError’)); // 设置一个用户定义的错误处理函数
set_exception_handler(array(‘Debug’,'appException’)); //自定义异常处理。

<?php
function test() {
    echo "test()";
}
register_shutdown_function(array("test"));
echo "show: ";
?>

show: test()    

<?php
    class ClassDemo {
        public function __construct() {
            register_shutdown_function(array($this, "f"));
        }
 
        public function f() {
            echo "f()";
        }
    }
 
    $demo = new ClassDemo();
    echo "before </br>";
?>

before
f()

?php
function f($str) {
        echo $str."<br>";
}
 
register_shutdown_function("f","hello");

    class ClassDemo {
        public function __construct() {
            register_shutdown_function(array($this, "f"),"hello");
        }
 
        public function f($str) {
            echo "f():".$str;
        }
    }
 
   $demo = new ClassDemo();
   echo "before </br>";   
?>