(PHP 5, PHP 7, PHP 8)
ReflectionClass::isAbstract — 检查类是否是抽象类（abstract）
此函数没有参数。
示例 #1 ReflectionClass::isAbstract() 示例
<?php
class TestClass { }
abstract class TestAbstractClass { }
$testClass = new ReflectionClass('TestClass');
$abstractClass = new ReflectionClass('TestAbstractClass');
var_dump($testClass->isAbstract());
var_dump($abstractClass->isAbstract());
?>以上示例会输出：
bool(false) bool(true)
For interfaces and traits :<?phpinterface TestInterface { }trait TestTrait { }$interfaceClass = new ReflectionClass('TestInterface');$traitClass = new ReflectionClass('TestTrait');var_dump($interfaceClass->isAbstract());var_dump($traitClass->isAbstract());?>Using PHP versions 5.4- to 5.6, the above example will output:bool(false)bool(true)Using PHP versions 7.0+, the above example will output:bool(false)bool(false)For traits:- ReflectionClass::isAbstract returns true if the trait contains at least one un-implemented abstract method, including those declared into used traits.- ReflectionClass::isAbstract returns false if all methods are implemented.<?phptrait TI { public function has() {} }var_dump((new ReflectionClass(TI::class))->isAbstract());trait TT { abstract public function has(); }trait T { use TT; }var_dump((new ReflectionClass(T::class))->isAbstract());?>Will output:bool(false)bool(true)For interfaces:- ReflectionClass::isAbstract returns true if the interface contains at least one method, including into its extended interfaces.- ReflectionClass::isAbstract returns false if the interface contains no method.<?phpinterface AI {}var_dump((new ReflectionClass(AI::class))->isAbstract());interface II { public function has(); }interface I extends II {}var_dump((new ReflectionClass(I::class))->isAbstract());?>Will output:bool(false)bool(true)For classes:- Reflection::isAbstract returns true if the class is marked as abstract, no matter if it contains abstract methods or not.