首页
所有分类
TAGS
文字工具 EMOJI BIBLE
编程 PHP

PHP面向对象程序设计之类与反射API详解

Posted in PHP onDecember 02, 2016

本文实例讲述了PHP面向对象程序设计之类与反射API。分享给大家供大家参考，具体如下：

了解类

class_exists验证类是否存在

<?php
// TaskRunner.php
$classname = "Task";
$path = "tasks/{$classname}.php";
if ( ! file_exists( $path ) ) {
  throw new Exception( "No such file as {$path}" ); //抛出异常,类文件不存在
}
require_once( $path );
$qclassname = "tasks\\$classname";
if ( ! class_exists( $qclassname ) ) {
  throw new Exception( "No such class as $qclassname" ); //抛出异常,类不存在Fatal error: Uncaught exception 'Exception' with message 'No such class as tasks\Task'
Stack trace:
#0 {main}
}
$myObj = new $qclassname();
$myObj->doSpeak();
?>

get_class 检查对象的类 instanceof 验证对象是否属于某个类

<?php
class CdProduct {}
function getProduct() {
  return new CdProduct(  "Exile on Coldharbour Lane",
                "The", "Alabama 3", 10.99, 60.33 ); // 返回一个类对象
}
$product = getProduct();
if ( get_class( $product ) == 'CdProduct' ) {
  print "\$product is a CdProduct object\n";
}
?>
<?php
class CdProduct {}
function getProduct() {
  return new CdProduct(  "Exile on Coldharbour Lane",
                "The", "Alabama 3", 10.99, 60.33 );
}
$product = getProduct();
if ( $product instanceof CdProduct ) {
  print "\$product is a CdProduct object\n";
}
?>

get_class_methods 得到类中所有的方法列表,只获取public的方法，protected，private的方法获取不到。默认的就是public。

<?php
class CdProduct {
  function __construct() { }
  function getPlayLength() { }
  function getSummaryLine() { }
  function getProducerFirstName() { }
  function getProducerMainName() { }
  function setDiscount() { }
  function getDiscount() { }
  function getTitle() { }
  function getPrice() { }
  function getProducer() { }
}
print_r( get_class_methods( 'CdProduct' ) );
?>

output:

Array
(
  [0] => __construct
  [1] => getPlayLength
  [2] => getSummaryLine
  [3] => getProducerFirstName
  [4] => getProducerMainName
  [5] => setDiscount
  [6] => getDiscount
  [7] => getTitle
  [8] => getPrice
  [9] => getProducer
)

更多验证

<?php
class ShopProduct {}
interface incidental {};
class CdProduct extends ShopProduct implements incidental {
  public $coverUrl;
  function __construct() { }
  function getPlayLength() { }
  function getSummaryLine() { }
  function getProducerFirstName() { }
  function getProducerMainName() { }
  function setDiscount() { }
  function getDiscount() { }
  function getTitle() { return "title\n"; }
  function getPrice() { }
  function getProducer() { }
}
function getProduct() {
  return new CdProduct();
}
$product = getProduct(); // acquire an object
$method = "getTitle";   // define a method name
print $product->$method(); // invoke the method
if ( in_array( $method, get_class_methods( $product ) ) ) {
  print $product->$method(); // invoke the method
}
if ( is_callable( array( $product, $method) ) ) {
  print $product->$method(); // invoke the method
}
if ( method_exists( $product, $method ) ) {
  print $product->$method(); // invoke the method
}
print_r( get_class_vars( 'CdProduct' ) );
if ( is_subclass_of( $product, 'ShopProduct' ) ) {
  print "CdProduct is a subclass of ShopProduct\n";
}
if ( is_subclass_of( $product, 'incidental' ) ) {
  print "CdProduct is a subclass of incidental\n";
}
if ( in_array( 'incidental', class_implements( $product )) ) {
  print "CdProduct is an interface of incidental\n";
}
?>

output:

title
title
title
title
Array
(
  [coverUrl] =>
)
CdProduct is a subclass of ShopProduct
CdProduct is a subclass of incidental
CdProduct is an interface of incidental

__call方法

<?php
class OtherShop {
  function thing() {
    print "thing\n";
  }
  function andAnotherthing() {
    print "another thing\n";
  }
}
class Delegator {
  private $thirdpartyShop;
  function __construct() {
    $this->thirdpartyShop = new OtherShop();
  }
  function __call( $method, $args ) { // 当调用未命名方法时执行call方法
    if ( method_exists( $this->thirdpartyShop, $method ) ) {
      return $this->thirdpartyShop->$method( );
    }
  }
}
$d = new Delegator();
$d->thing();
?>

output:

thing

传参使用

<?php
class OtherShop {
  function thing() {
    print "thing\n";
  }
  function andAnotherthing( $a, $b ) {
    print "another thing ($a, $b)\n";
  }
}
class Delegator {
  private $thirdpartyShop;
  function __construct() {
    $this->thirdpartyShop = new OtherShop();
  }
  function __call( $method, $args ) {
    if ( method_exists( $this->thirdpartyShop, $method ) ) {
      return call_user_func_array(
            array( $this->thirdpartyShop,
              $method ), $args );
    }
  }
}
$d = new Delegator();
$d->andAnotherThing( "hi", "hello" );
?>

output:

another thing (hi, hello)

反射API

fullshop.php

<?php
class ShopProduct {
  private $title;
  private $producerMainName;
  private $producerFirstName;
  protected $price;
  private $discount = 0;
  public function __construct(  $title, $firstName,
              $mainName, $price ) {
    $this->title       = $title;
    $this->producerFirstName = $firstName;
    $this->producerMainName = $mainName;
    $this->price       = $price;
  }
  public function getProducerFirstName() {
    return $this->producerFirstName;
  }
  public function getProducerMainName() {
    return $this->producerMainName;
  }
  public function setDiscount( $num ) {
    $this->discount=$num;
  }
  public function getDiscount() {
    return $this->discount;
  }
  public function getTitle() {
    return $this->title;
  }
  public function getPrice() {
    return ($this->price - $this->discount);
  }
  public function getProducer() {
    return "{$this->producerFirstName}".
        " {$this->producerMainName}";
  }
  public function getSummaryLine() {
    $base = "{$this->title} ( {$this->producerMainName}, ";
    $base .= "{$this->producerFirstName} )";
    return $base;
  }
}
class CdProduct extends ShopProduct {
  private $playLength = 0;
  public function __construct(  $title, $firstName,
              $mainName, $price, $playLength=78 ) {
    parent::__construct(  $title, $firstName,
                $mainName, $price );
    $this->playLength = $playLength;
  }
  public function getPlayLength() {
    return $this->playLength;
  }
  public function getSummaryLine() {
    $base = parent::getSummaryLine();
    $base .= ": playing time - {$this->playLength}";
    return $base;
  }
}
class BookProduct extends ShopProduct {
  private $numPages = 0;
  public function __construct(  $title, $firstName,
              $mainName, $price, $numPages ) {
    parent::__construct(  $title, $firstName,
                $mainName, $price );
    $this->numPages = $numPages;
  }
  public function getNumberOfPages() {
    return $this->numPages;
  }
  public function getSummaryLine() {
    $base = parent::getSummaryLine();
    $base .= ": page count - {$this->numPages}";
    return $base;
  }
  public function getPrice() {
    return $this->price;
  }
}
/*
$product1 = new CdProduct("cd1", "bob", "bobbleson", 4, 50 );
print $product1->getSummaryLine()."\n";
$product2 = new BookProduct("book1", "harry", "harrelson", 4, 30 );
print $product2->getSummaryLine()."\n";
*/
?>
<?php
require_once "fullshop.php";
$prod_class = new ReflectionClass( 'CdProduct' );
Reflection::export( $prod_class );
?>

output:

Class [ <user> class CdProduct extends ShopProduct ] {
 @@ D:\xampp\htdocs\popp-code\5\fullshop.php 53-73
 - Constants [0] {
 }
 - Static properties [0] {
 }
 - Static methods [0] {
 }
 - Properties [2] {
  Property [ <default> private $playLength ]
  Property [ <default> protected $price ]
 }
 - Methods [10] {
  Method [ <user, overwrites ShopProduct, ctor> public method __construct ] {
   @@ D:\xampp\htdocs\popp-code\5\fullshop.php 56 - 61
   - Parameters [5] {
    Parameter #0 [ <required> $title ]
    Parameter #1 [ <required> $firstName ]
    Parameter #2 [ <required> $mainName ]
    Parameter #3 [ <required> $price ]
    Parameter #4 [ <optional> $playLength = 78 ]
   }
  }
  Method [ <user> public method getPlayLength ] {
   @@ D:\xampp\htdocs\popp-code\5\fullshop.php 63 - 65
  }
  Method [ <user, overwrites ShopProduct, prototype ShopProduct> public method getSummaryLine ] {
   @@ D:\xampp\htdocs\popp-code\5\fullshop.php 67 - 71
  }
  Method [ <user, inherits ShopProduct> public method getProducerFirstName ] {
   @@ D:\xampp\htdocs\popp-code\5\fullshop.php 17 - 19
  }
  Method [ <user, inherits ShopProduct> public method getProducerMainName ] {
   @@ D:\xampp\htdocs\popp-code\5\fullshop.php 21 - 23
  }
  Method [ <user, inherits ShopProduct> public method setDiscount ] {
   @@ D:\xampp\htdocs\popp-code\5\fullshop.php 25 - 27
   - Parameters [1] {
    Parameter #0 [ <required> $num ]
   }
  }
  Method [ <user, inherits ShopProduct> public method getDiscount ] {
   @@ D:\xampp\htdocs\popp-code\5\fullshop.php 29 - 31
  }
  Method [ <user, inherits ShopProduct> public method getTitle ] {
   @@ D:\xampp\htdocs\popp-code\5\fullshop.php 33 - 35
  }
  Method [ <user, inherits ShopProduct> public method getPrice ] {
   @@ D:\xampp\htdocs\popp-code\5\fullshop.php 37 - 39
  }
  Method [ <user, inherits ShopProduct> public method getProducer ] {
   @@ D:\xampp\htdocs\popp-code\5\fullshop.php 41 - 44
  }
 }
}

点评：把类看的透彻的一塌糊涂，比var_dump强多了。哪些属性，继承了什么类。类中的方法哪些是自己的，哪些是重写的，哪些是继承的，一目了然。

查看类数据

<?php
require_once("fullshop.php");
function classData( ReflectionClass $class ) {
 $details = "";
 $name = $class->getName();
 if ( $class->isUserDefined() ) {
  $details .= "$name is user defined\n";
 }
 if ( $class->isInternal() ) {
  $details .= "$name is built-in\n";
 }
 if ( $class->isInterface() ) {
  $details .= "$name is interface\n";
 }
 if ( $class->isAbstract() ) {
  $details .= "$name is an abstract class\n";
 }
 if ( $class->isFinal() ) {
  $details .= "$name is a final class\n";
 }
 if ( $class->isInstantiable() ) {
  $details .= "$name can be instantiated\n";
 } else {
  $details .= "$name can not be instantiated\n";
 }
 return $details;
}
$prod_class = new ReflectionClass( 'CdProduct' );
print classData( $prod_class );
?>

output:

CdProduct is user defined
CdProduct can be instantiated

查看方法数据

<?php
require_once "fullshop.php";
$prod_class = new ReflectionClass( 'CdProduct' );
$methods = $prod_class->getMethods();
foreach ( $methods as $method ) {
 print methodData( $method );
 print "\n----\n";
}
function methodData( ReflectionMethod $method ) {
 $details = "";
 $name = $method->getName();
 if ( $method->isUserDefined() ) {
  $details .= "$name is user defined\n";
 }
 if ( $method->isInternal() ) {
  $details .= "$name is built-in\n";
 }
 if ( $method->isAbstract() ) {
  $details .= "$name is abstract\n";
 }
 if ( $method->isPublic() ) {
  $details .= "$name is public\n";
 }
 if ( $method->isProtected() ) {
  $details .= "$name is protected\n";
 }
 if ( $method->isPrivate() ) {
  $details .= "$name is private\n";
 }
 if ( $method->isStatic() ) {
  $details .= "$name is static\n";
 }
 if ( $method->isFinal() ) {
  $details .= "$name is final\n";
 }
 if ( $method->isConstructor() ) {
  $details .= "$name is the constructor\n";
 }
 if ( $method->returnsReference() ) {
  $details .= "$name returns a reference (as opposed to a value)\n";
 }
 return $details;
}
?>

output:

__construct is user defined
__construct is public
__construct is the constructor
----
getPlayLength is user defined
getPlayLength is public
----
getSummaryLine is user defined
getSummaryLine is public
----
getProducerFirstName is user defined
getProducerFirstName is public
----
getProducerMainName is user defined
getProducerMainName is public
----
setDiscount is user defined
setDiscount is public
----
getDiscount is user defined
getDiscount is public
----
getTitle is user defined
getTitle is public
----
getPrice is user defined
getPrice is public
----
getProducer is user defined
getProducer is public

获取构造函数参数情况

<?php
require_once "fullshop.php";
$prod_class = new ReflectionClass( 'CdProduct' );
$method = $prod_class->getMethod( "__construct" );
$params = $method->getParameters();
foreach ( $params as $param ) {
  print argData( $param )."\n";
}
function argData( ReflectionParameter $arg ) {
 $details = "";
 $declaringclass = $arg->getDeclaringClass();
 $name = $arg->getName();
 $class = $arg->getClass();
 $position = $arg->getPosition();
 $details .= "\$$name has position $position\n";
 if ( ! empty( $class ) ) {
  $classname = $class->getName();
  $details .= "\$$name must be a $classname object\n";
 }
 if ( $arg->isPassedByReference() ) {
  $details .= "\$$name is passed by reference\n";
 }
 if ( $arg->isDefaultValueAvailable() ) {
  $def = $arg->getDefaultValue();
  $details .= "\$$name has default: $def\n";
 }
 if ( $arg->allowsNull() ) {
  $details .= "\$$name can be null\n";
 }
 return $details;
}
?>

output:

$title has position 0
$title can be null
$firstName has position 1
$firstName can be null
$mainName has position 2
$mainName can be null
$price has position 3
$price can be null
$playLength has position 4
$playLength has default: 78
$playLength can be null

希望本文所述对大家PHP程序设计有所帮助。

PHP面向对象程序设计之类与反射API详解

- Author -

牛逼的霍啸林

声明：登载此文出于传递更多信息之目的，并不意味着赞同其观点或证实其描述。

PHP 相关文章推荐
Get或Post提交值的非法数据处理
Oct 09 PHP
40个迹象表明你还是PHP菜鸟
Sep 29 PHP
spl_autoload_register与autoload的区别详解
Jun 03 PHP
解决PHP4.0 和 PHP5.0类构造函数的兼容问题
Aug 01 PHP
php中json_encode UTF-8中文乱码的更好解决方法
Sep 28 PHP
php启用sphinx全文搜索的实现方法
Dec 24 PHP
php通过正则表达式记取数据来读取xml的方法
Mar 09 PHP
Yii2 assets清除缓存的方法
May 16 PHP
php简单截取字符串代码示例
Oct 19 PHP
PHP4和PHP5版本下解析XML文档的操作方法实例分析
May 20 PHP
详解json在php中的应用
Sep 30 PHP
PHP中常用的三种设计模式详解【单例模式、工厂模式、观察者模式】
Jun 14 PHP
PHP面向对象程序设计之对象生成方法详解
Dec 02 #PHP
PHP面向对象程序设计组合模式与装饰模式详解
Dec 02 #PHP
PHP与jquery实时显示网站在线人数实例详解
Dec 02 #PHP
谈谈php对接芝麻信用踩的坑
Dec 01 #PHP
PHP自定义函数获取汉字首字母的方法
Dec 01 #PHP
phpmailer绑定邮箱的实现方法
Dec 01 #PHP
thinkPHP实现多字段模糊匹配查询的方法
Dec 01 #PHP
蓝牙耳机(1) HarmonyOS(1) 鸿蒙(2) Debian(1) win7(2) 蓝牙(1) 虚拟键盘(1) RustDesk(1) 华为(1) 鸿蒙3.0(1)
You might like
codeigniter框架The URI you submitted has disallowed characters错误解决方法
2014/05/06 PHP
用 Composer构建自己的 PHP 框架之设计 MVC
2014/10/30 PHP
Nginx下配置codeigniter框架方法
2015/04/07 PHP
PHP strcmp()和strcasecmp()的区别实例
2016/11/05 PHP
使用JavaScript+canvas实现图片裁剪
2015/01/30 Javascript
js+html5实现canvas绘制圆形图案的方法
2015/06/05 Javascript
JS控制表单提交的方法
2015/07/09 Javascript
JavaScript计划任务后台运行的方法
2015/12/18 Javascript
jQuery插件实现带圆点的焦点图片轮播切换
2016/01/18 Javascript
jQuery 如何实现一个滑动按钮开关
2016/12/01 Javascript
vue2的todolist入门小项目的详细解析
2017/05/11 Javascript
Easyui在treegrid添加控件的实现方法
2017/06/23 Javascript
nodejs构建本地web测试服务器 如何解决访问静态资源问题
2017/07/14 NodeJs
JavaScript实现异步图像上传功能
2018/07/12 Javascript
在axios中使用params传参的时候传入数组的方法
2018/09/25 Javascript
javascript实现异形滚动轮播
2019/11/28 Javascript
javascript设计模式 ? 访问者模式原理与用法实例分析
2020/04/26 Javascript
Echarts.js无法引入问题解决方案
2020/10/30 Javascript
关于uniApp editor微信滑动问题
2021/01/15 Javascript
[52:32]完美世界DOTA2联赛PWL S2 Magma vs LBZS 第三场 11.18
2020/11/18 DOTA
python字符串循环左移
2019/03/08 Python
Python pip替换为阿里源的方法步骤
2019/07/02 Python
Python如何调用JS文件中的函数
2019/08/16 Python
django框架ModelForm组件用法详解
2019/12/11 Python
Pytorch中.new()的作用详解
2020/02/18 Python
Python实现一个优先级队列的方法
2020/07/31 Python
一份婚庆公司创业计划书
2014/01/11 职场文书
信息专业大学生自我评价分享
2014/01/17 职场文书
物流专员岗位职责
2014/02/17 职场文书
和睦家庭事迹
2014/05/14 职场文书
中药学专业毕业生推荐信
2014/07/10 职场文书
挂职锻炼个人总结
2015/03/05 职场文书
入党介绍人意见怎么写
2015/06/03 职场文书
爱国教育主题班会
2015/08/14 职场文书
mysql分表之后如何平滑上线详解
2021/11/01 MySQL
搭建Yolov5服务器
2022/04/30 Servers