这里有新鲜出炉的 PHP 教程,程序狗速度看过来!
PHP(外文名: Hypertext Preprocessor,中文名:"超文本预处理器")是一种通用开源脚本语言。语法吸收了 C 语言、Java 和 Perl 的特点,入门门槛较低,易于学习,使用广泛,主要适用于 Web 开发领域。PHP 的文件后缀名为 php。
这篇文章主要介绍了 PHP 面向对象程序设计之类与反射 API, 结合实例形式较为详细的分析了类的验证、检查、传参及反射 API 等概念与操作技巧, 需要的朋友可以参考下
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。
来源: http://www.phperz.com/article/17/0802/340959.html