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