blocks|key|1456202|text|PHP还不支持多类继承，但是它支持多接口继承。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1456203|有关示例，请参阅http://www.hudzilla.org/php/6_17_0.php。|offset|length|1456204|entityMap|0|LINK|mutability|MUTABLE|url|http://www.hudzilla.org/php/6_17_0.php^0|0|8|12|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

PHP does not yet support multiple class inheritance, it does however support multiple interface inheritance.

See <a href="http://www.hudzilla.org/php/6_17_0.php" rel="nofollow noreferrer">http://www.hudzilla.org/php/6_17_0.php</a> for some examples.

blocks|key|1671205|text|您不能拥有扩展两个基类的类。您不能拥有以下内容：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671206|//+this+is+NOT+allowed+(for+all+you+google+speeders)
Matron+extends+Nurse,+HumanEntity|code-block|syntax|javascript|1671207|然而，你可以有一个层次结构，如下所示。|1671208|Matron+extends+Nurse++++
Consultant+extends+Doctor

Nurse+extends+HumanEntity
Doctor+extends+HumanEntity

HumanEntity+extends+DatabaseTable
DatabaseTable+extends+AbstractTable|1671209|诸若此类。|1671210|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

You cannot have a class that extends two base classes. You could not have the following:
<pre><code>// this is NOT allowed (for all you google speeders)
Matron extends Nurse, HumanEntity
</code></pre>
You could however have a hierarchy as follows...
<pre><code>Matron extends Nurse 
Consultant extends Doctor

Nurse extends HumanEntity
Doctor extends HumanEntity

HumanEntity extends DatabaseTable
DatabaseTable extends AbstractTable
</code></pre>
and so on.

blocks|key|1456315|text|类不仅仅是方法的集合。一个类应该表示一个抽象的概念，既有状态(字段)，也有改变状态的行为(方法)。仅仅使用继承来获得一些所需的行为听起来像是糟糕的面向对象设计，也正是许多语言不允许多重继承的原因:为了防止“意大利面式继承”，即扩展3个类，因为每个类都有一个你需要的方法，最后得到一个继承了100个方法和20个字段的类，但只使用了其中的5个。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1456316|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Classes are not meant to be just collections of methods. A class is supposed to represent an abstract concept, with both state (fields) and behaviour (methods) which changes the state. Using inheritance just to get some desired behaviour sounds like bad OO design, and exactly the reason why many languages disallow multiple inheritance: in order to prevent "spaghetti inheritance", i.e. extending 3 classes because each has a method you need, and ending up with a class that inherits 100 method and 20 fields, yet only ever uses 5 of them.

blocks|key|1671349|text|如果你真的想在PHP5.3中伪造多重继承，你可以使用神奇的函数__call()。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671350|这是丑陋的，尽管它从A级用户的角度来看是有效的：|1671351|class+B+{
++++public+function+method_from_b($s)+{
++++++++echo+$s;
++++}
}

class+C+{
++++public+function+method_from_c($s)+{
++++++++echo+$s;
++++}
}

class+A+extends+B
{
++private+$c;
++++
++public+function+__construct()
++{
++++$this->c+=+new+C;
++}
++++
++//+fake+"extends+C"+using+magic+function
++public+function+__call($method,+$args)
++{
++++$this->c->$method($args[0]);
++}
}


$a+=+new+A;
$a->method_from_b("abc");
$a->method_from_c("def");|code-block|syntax|javascript|1671352|打印"abcdef“|1671353|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|O|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

If you really want to fake multiple inheritance in PHP 5.3, you can use the magic function __call().
This is ugly though it works from class A user's point of view :
<pre><code>class B {
 public function method_from_b($s) {
 echo $s;
 }
}

class C {
 public function method_from_c($s) {
 echo $s;
 }
}

class A extends B
{
 private $c;
 
 public function __construct()
 {
 $this-&gt;c = new C;
 }
 
 // fake &quot;extends C&quot; using magic function
 public function __call($method, $args)
 {
 $this-&gt;c-&gt;$method($args[0]);
 }
}


$a = new A;
$a-&gt;method_from_b(&quot;abc&quot;);
$a-&gt;method_from_c(&quot;def&quot;);
</code></pre>
Prints &quot;abcdef&quot;

blocks|key|1671401|text|我读过几篇文章，劝阻项目中的继承(相对于库/框架)，并鼓励对接口进行编程，而不是反对实现。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671402|他们还通过组合来提倡面向对象:如果你需要a和b类中的函数，让c拥有这种类型的成员/字段：|1671403|class+C
{
++++private+$a,+$b;

++++public+function+__construct($x,+$y)
++++{
++++++++$this->a+=+new+A(42,+$x);
++++++++$this->b+=+new+B($y);
++++}

++++protected+function+DoSomething()
++++{
++++++++$this->a->Act();
++++++++$this->b->Do();
++++}
}|code-block|syntax|javascript|1671404|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

I have read several articles discouraging inheritance in projects (as opposed to libraries/frameworks), and encouraging to program agaisnt interfaces, no against implementations. 
They also advocate OO by composition: if you need the functions in class a and b, make c having members/fields of this type:

<pre><code>class C
{
 private $a, $b;

 public function __construct($x, $y)
 {
 $this-&gt;a = new A(42, $x);
 $this-&gt;b = new B($y);
 }

 protected function DoSomething()
 {
 $this-&gt;a-&gt;Act();
 $this-&gt;b-&gt;Do();
 }
}
</code></pre>

blocks|key|1671429|text|我相信，很快就会有增加mix-in的计划。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671430|但在此之前，请遵循公认的答案。你可以把它抽象出来，使之成为一个“可扩展”的类：|1671431|class+Extendable{
++private+$extender=array();

++public+function+addExtender(Extender+$obj){
++++$this->extenders[]+=+$obj;
++++$obj->setExtendee($this);
++}

++public+function+__call($name,+$params){
++++foreach($this->extenders+as+$extender){
+++++++//do+reflection+to+see+if+extender+has+this+method+with+this+argument+count
+++++++if+(method_exists($extender,+$name)){
++++++++++return+call_user_func_array(array($extender,+$name),+$params);
+++++++}
++++}
++}
}


$foo+=+new+Extendable();
$foo->addExtender(new+OtherClass());
$foo->other_class_method();|code-block|syntax|javascript|1671432|请注意，在这个模型中，"OtherClass“可以”了解“$foo。OtherClass需要有一个名为"setExtendee“的公共函数来建立这种关系。然后，如果它的方法是从$foo调用的，它就可以在内部访问$foo。然而，它不会像真正的扩展类那样访问任何私有/受保护的方法/变量。|1671433|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|O|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

There are plans for adding mix-ins soon, I believe.

But until then, go with the accepted answer. You can abstract that out a bit to make an "extendable" class:

<pre><code>class Extendable{
 private $extender=array();

 public function addExtender(Extender $obj){
 $this-&gt;extenders[] = $obj;
 $obj-&gt;setExtendee($this);
 }

 public function __call($name, $params){
 foreach($this-&gt;extenders as $extender){
 //do reflection to see if extender has this method with this argument count
 if (method_exists($extender, $name)){
 return call_user_func_array(array($extender, $name), $params);
 }
 }
 }
}


$foo = new Extendable();
$foo-&gt;addExtender(new OtherClass());
$foo-&gt;other_class_method();
</code></pre>

Note that in this model "OtherClass" gets to 'know' about $foo. OtherClass needs to have a public function called "setExtendee" to set up this relationship. Then, if it's methods are invoked from $foo, it can access $foo internally. It will not, however, get access to any private/protected methods/variables like a real extended class would.

blocks|key|1671450|text|由于不知道你到底想要实现什么，我建议研究一下重新设计你的应用程序以使用组合而不是继承的可能性。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671451|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Not knowing exactly what you're trying to achieve, I would suggest looking into the possibility of redesigning you application to use composition rather than inheritance in this case.

blocks|key|1671477|text|最好的办法就是让父类具有函数...例如，将此所有功能添加到父级。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671478|并“下移”所有使用它的类。我需要重写函数，这些函数是特定的。|1671479|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

Always good idea is to make parent class, with functions ... i.e. add this all functionality to parent. 

And "move" all classes that use this hierarchically down. I need - rewrite functions, which are specific.

blocks|key|1671517|text|您可以使用特征，希望在PHP5.4中可以使用。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671518|特征是PHP等单继承语言中代码重用的一种机制。特征旨在通过使开发人员能够在位于不同类层次结构中的几个独立类中自由重用方法集来减少单一继承的某些限制。特征和类组合的语义以一种方式定义，它降低了复杂性，并避免了与多重继承和混合相关的典型问题。|1671519|它们在支持更好的组合和重用方面的潜力得到了认可，因此它们集成在较新版本的语言中，如Perl6、Squeak、Scala、Slate和要塞。特征也被移植到Java和C#。|1671520|更多信息：https://wiki.php.net/rfc/traits|offset|length|1671521|entityMap|0|LINK|mutability|MUTABLE|url|https://wiki.php.net/rfc/traits^0|0|0|0|5|V|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|S|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|T|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|U|8|@]|9|@$H|V|I|W|1|X]]|A|$]]|$1|J|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|K|$L|$5|M|N|O|A|$P|Q]]]]

You could use traits, which, hopefully, will be available from PHP 5.4.

Traits is a mechanism for code reuse in single inheritance languages such as PHP. A Trait is intended to reduce some limitations of single inheritance by enabling a developer to reuse sets of methods freely in several independent classes living in different class hierarchies. The semantics of the combination of Traits and classes is defined in a way, which reduces complexity and avoids the typical problems associated with multiple inheritance and Mixins.

They are recognized for their potential in supporting better composition and reuse, hence their integration in newer versions of languages such as Perl 6, Squeak, Scala, Slate and Fortress. Traits have also been ported to Java and C#.

More information: <a href="https://wiki.php.net/rfc/traits" rel="noreferrer">https://wiki.php.net/rfc/traits</a>

blocks|key|1456582|text|我刚刚用以下方法解决了我的“多重继承”问题：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1456583|class+Session+{
++++public+$username;
}

class+MyServiceResponsetype+{
++++protected+$only_avaliable_in_response;
}

class+SessionResponse+extends+MyServiceResponsetype+{
++++/**+has+shared+$only_avaliable_in_response+*/

++++public+$session;

++++public+function+__construct(Session+$session)+{
++++++$this->session+=+$session;
++++}

}|code-block|syntax|javascript|1456584|这样，我就有能力在扩展了MyServiceResponsetype的SessionResponse中操作会话，而且仍然能够单独处理会话。|1456585|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

I just solved my "multiple inheritance" problem with:

<pre><code>class Session {
 public $username;
}

class MyServiceResponsetype {
 protected $only_avaliable_in_response;
}

class SessionResponse extends MyServiceResponsetype {
 /** has shared $only_avaliable_in_response */

 public $session;

 public function __construct(Session $session) {
 $this-&gt;session = $session;
 }

}
</code></pre>

This way I have the power to manipulate session inside a SessionResponse which extends MyServiceResponsetype still being able to handle Session by itself.

blocks|key|1456629|text|如果要检查函数是否为公共函数，请参阅此主题：https://stackoverflow.com/a/4160928/2226755|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1456630|并使用call_user_func_array(...)方法用于多个或不多个参数。|1456631|如下所示：|1456632|class+B+{
++++public+function+method_from_b($s)+{
++++++++echo+$s;
++++}
}

class+C+{
++++public+function+method_from_c($l,+$l1,+$l2)+{
++++++++echo+$l.$l1.$l2;
++++}
}

class+A+extends+B+{
++++private+$c;

++++public+function+__construct()+{
++++++++$this->c+=+new+C;
++++}

++++public+function+__call($method,+$args)+{
++++++++if+(method_exists($this->c,+$method))+{
++++++++++++$reflection+=+new+ReflectionMethod($this->c,+$method);
++++++++++++if+(!$reflection->isPublic())+{
++++++++++++++++throw+new+RuntimeException("Call+to+not+public+method+".get_class($this)."::$method()");
++++++++++++}

++++++++++++return+call_user_func_array(array($this->c,+$method),+$args);
++++++++}+else+{
++++++++++++throw+new+RuntimeException("Call+to+undefined+method+".get_class($this)."::$method()");
++++++++}
++++}
}


$a+=+new+A;
$a->method_from_b("abc");
$a->method_from_c("d",+"e",+"f");|code-block|syntax|javascript|1456633|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/4160928/2226755^0|M|17|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|6|7|Y|8|@]|9|@]|C|$]]|$1|F|3|G|5|6|7|Z|8|@]|9|@]|C|$]]|$1|H|3|I|5|J|7|10|8|@]|9|@]|C|$K|L]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|C|$]]]|N|$O|$5|P|Q|R|C|$S|T]]]]

If you want to check if a function is public see this topic : <a href="https://stackoverflow.com/a/4160928/2226755">https://stackoverflow.com/a/4160928/2226755</a>

And use call_user_func_array(...) method for many or not arguments.

Like this :

<pre><code>class B {
 public function method_from_b($s) {
 echo $s;
 }
}

class C {
 public function method_from_c($l, $l1, $l2) {
 echo $l.$l1.$l2;
 }
}

class A extends B {
 private $c;

 public function __construct() {
 $this-&gt;c = new C;
 }

 public function __call($method, $args) {
 if (method_exists($this-&gt;c, $method)) {
 $reflection = new ReflectionMethod($this-&gt;c, $method);
 if (!$reflection-&gt;isPublic()) {
 throw new RuntimeException("Call to not public method ".get_class($this)."::$method()");
 }

 return call_user_func_array(array($this-&gt;c, $method), $args);
 } else {
 throw new RuntimeException("Call to undefined method ".get_class($this)."::$method()");
 }
 }
}


$a = new A;
$a-&gt;method_from_b("abc");
$a-&gt;method_from_c("d", "e", "f");
</code></pre>

blocks|key|1456649|text|<?php
//+what+if+we+want+to+extend+more+than+one+class?

abstract+class+ExtensionBridge
{
++++//+array+containing+all+the+extended+classes
++++private+$_exts+=+array();
++++public+$_this;

++++function+__construct()+{$_this+=+$this;}

++++public+function+addExt($object)
++++{
++++++++$this->_exts[]=$object;
++++}

++++public+function+__get($varname)
++++{
++++++++foreach($this->_exts+as+$ext)
++++++++{
++++++++++++if(property_exists($ext,$varname))
++++++++++++return+$ext->$varname;
++++++++}
++++}

++++public+function+__call($method,$args)
++++{
++++++++foreach($this->_exts+as+$ext)
++++++++{
++++++++++++if(method_exists($ext,$method))
++++++++++++return+call_user_method_array($method,$ext,$args);
++++++++}
++++++++throw+new+Exception("This+Method+{$method}+doesn't+exists");
++++}


}

class+Ext1
{
++++private+$name="";
++++private+$id="";
++++public+function+setID($id){$this->id+=+$id;}
++++public+function+setName($name){$this->name+=+$name;}
++++public+function+getID(){return+$this->id;}
++++public+function+getName(){return+$this->name;}
}

class+Ext2
{
++++private+$address="";
++++private+$country="";
++++public+function+setAddress($address){$this->address+=+$address;}
++++public+function+setCountry($country){$this->country+=+$country;}
++++public+function+getAddress(){return+$this->address;}
++++public+function+getCountry(){return+$this->country;}
}

class+Extender+extends+ExtensionBridge
{
++++function+__construct()
++++{
++++++++parent::addExt(new+Ext1());
++++++++parent::addExt(new+Ext2());
++++}

++++public+function+__toString()
++++{
++++++++return+$this->getName().',+from:+'.$this->getCountry();
++++}
}

$o+=+new+Extender();
$o->setName("Mahdi");
$o->setCountry("Al-Ahwaz");
echo+$o;
?>|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1456650|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>&lt;?php
// what if we want to extend more than one class?

abstract class ExtensionBridge
{
 // array containing all the extended classes
 private $_exts = array();
 public $_this;

 function __construct() {$_this = $this;}

 public function addExt($object)
 {
 $this-&gt;_exts[]=$object;
 }

 public function __get($varname)
 {
 foreach($this-&gt;_exts as $ext)
 {
 if(property_exists($ext,$varname))
 return $ext-&gt;$varname;
 }
 }

 public function __call($method,$args)
 {
 foreach($this-&gt;_exts as $ext)
 {
 if(method_exists($ext,$method))
 return call_user_method_array($method,$ext,$args);
 }
 throw new Exception("This Method {$method} doesn't exists");
 }


}

class Ext1
{
 private $name="";
 private $id="";
 public function setID($id){$this-&gt;id = $id;}
 public function setName($name){$this-&gt;name = $name;}
 public function getID(){return $this-&gt;id;}
 public function getName(){return $this-&gt;name;}
}

class Ext2
{
 private $address="";
 private $country="";
 public function setAddress($address){$this-&gt;address = $address;}
 public function setCountry($country){$this-&gt;country = $country;}
 public function getAddress(){return $this-&gt;address;}
 public function getCountry(){return $this-&gt;country;}
}

class Extender extends ExtensionBridge
{
 function __construct()
 {
 parent::addExt(new Ext1());
 parent::addExt(new Ext2());
 }

 public function __toString()
 {
 return $this-&gt;getName().', from: '.$this-&gt;getCountry();
 }
}

$o = new Extender();
$o-&gt;setName("Mahdi");
$o-&gt;setCountry("Al-Ahwaz");
echo $o;
?&gt;
</code></pre>

blocks|key|1671621|text|您可以使用PHP5.4发布的特性来实现这一点|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671622|这是给你的快速教程，http://culttt.com/2014/06/25/php-traits/|offset|length|1671623|entityMap|0|LINK|mutability|MUTABLE|url|http://culttt.com/2014/06/25/php-traits/^0|0|A|14|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

You are able to do that using Traits in PHP which announced as of PHP 5.4

Here is a quick tutorial for you, <a href="http://culttt.com/2014/06/25/php-traits/" rel="nofollow">http://culttt.com/2014/06/25/php-traits/</a>

blocks|key|1456722|text|多重继承似乎在接口级别起作用。我在php+5.6.1上做了一个测试。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1456723|下面是一个有效的代码：|1456724|<?php


interface+Animal
{
++++public+function+sayHello();
}


interface+HairyThing
{
++++public+function+plush();
}

interface+Dog+extends+Animal,+HairyThing
{
++++public+function+bark();
}


class+Puppy+implements+Dog
{
++++public+function+bark()
++++{
++++++++echo+"ouaf";
++++}

++++public+function+sayHello()
++++{
++++++++echo+"hello";
++++}

++++public+function+plush()
++++{
++++++++echo+"plush";
++++}


}


echo+PHP_VERSION;+//+5.6.1
$o+=+new+Puppy();
$o->bark();
$o->plush();
$o->sayHello();+//+displays:+5.6.16ouafplushhello|code-block|syntax|javascript|1456725|我不认为这是可能的，但我在Swift_Transport_IoBuffer类的SwiftMailer源代码中偶然发现了这一点，该类具有以下定义：|1456726|interface+Swift_Transport_IoBuffer+extends+Swift_InputByteStream,+Swift_OutputByteStream|1456727|我还没有玩过它，但我想分享一下可能会很有趣。|1456728|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|R|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|T|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|U|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|V|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

Multiple inheritance seems to work at the interface level.
I made a test on php 5.6.1.

Here is a working code:

<pre><code>&lt;?php


interface Animal
{
 public function sayHello();
}


interface HairyThing
{
 public function plush();
}

interface Dog extends Animal, HairyThing
{
 public function bark();
}


class Puppy implements Dog
{
 public function bark()
 {
 echo "ouaf";
 }

 public function sayHello()
 {
 echo "hello";
 }

 public function plush()
 {
 echo "plush";
 }


}


echo PHP_VERSION; // 5.6.1
$o = new Puppy();
$o-&gt;bark();
$o-&gt;plush();
$o-&gt;sayHello(); // displays: 5.6.16ouafplushhello
</code></pre>

I didn't think that was possible, but I stumbled upon in the SwiftMailer source code, in the Swift_Transport_IoBuffer class, which has the following definition: 

<pre><code>interface Swift_Transport_IoBuffer extends Swift_InputByteStream, Swift_OutputByteStream
</code></pre>

I didn't play with it yet, but I thought it might be interesting to share.

blocks|key|1456774|text|PHP作为一种编程语言的问题之一是，您只能拥有单一继承。这意味着一个类只能从另一个类继承。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1456775|然而，在很多情况下，从多个类继承将是有益的。例如，为了防止代码重复，可能需要从几个不同的类继承方法。|1456776|这个问题可能导致具有长期家族继承历史的类，这通常是没有意义的。|1456777|在PHP5.4中，语言添加了一个新特性，称为特征。特征有点像Mixin，因为它允许您将特征类混合到现有类中。这意味着您可以减少代码重复并获得好处，同时避免多重继承的问题。|1456778|Traits|offset|length|1456779|entityMap|0|LINK|mutability|MUTABLE|url|http://php.net/manual/en/language.oop5.traits.php^0|0|0|0|0|0|6|0|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|U|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|V|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|W|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|X|8|@]|9|@$J|Y|K|Z|1|10]]|A|$]]|$1|L|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|M|$N|$5|O|P|Q|A|$R|S]]]]

One of the problems of PHP as a programming language is the fact that you can only have single inheritance. This means a class can only inherit from one other class.

However, a lot of the time it would be beneficial to inherit from multiple classes. For example, it might be desirable to inherit methods from a couple of different classes in order to prevent code duplication.

This problem can lead to class that has a long family history of inheritance which often does not make sense.

In PHP 5.4 a new feature of the language was added known as Traits. A Trait is kind of like a Mixin in that it allows you to mix Trait classes into an existing class. This means you can reduce code duplication and get the benefits whilst avoiding the problems of multiple inheritance.

<a href="http://php.net/manual/en/language.oop5.traits.php" rel="nofollow noreferrer">Traits</a>

blocks|key|1671803|text|使用特征作为基类。然后在父类中使用它们。延伸它。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671804|trait+business{
++function+sell(){

++}

++function+buy(){

++}

++function+collectMoney(){
++}

}

trait+human{

+++function+think(){

+++}

+++function+speak(){

+++}

}

class+BusinessPerson{
++use+business;
++use+human;
++//+If+you+have+more+traits+bring+more
}


class+BusinessWoman+extends+BusinessPerson{

+++function+getPregnant(){

+++}

}


$bw+=+new+BusinessWoman();
$bw+->speak();
$bw->getPregnant();|code-block|syntax|javascript|1671805|现在看，商业女性逻辑上继承了商业和人类两者；|1671806|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Use traits as base classes. Then use them in a parent class. Extend it .

<pre><code>trait business{
 function sell(){

 }

 function buy(){

 }

 function collectMoney(){
 }

}

trait human{

 function think(){

 }

 function speak(){

 }

}

class BusinessPerson{
 use business;
 use human;
 // If you have more traits bring more
}


class BusinessWoman extends BusinessPerson{

 function getPregnant(){

 }

}


$bw = new BusinessWoman();
$bw -&gt;speak();
$bw-&gt;getPregnant();
</code></pre>

See now business woman logically inherited business and human both;

blocks|key|1671858|text|A类扩展了B+{}|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671859|B类扩展了C+{}|1671860|那么A已经扩展了B和C|1671861|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

class A extends B {}

class B extends C {}

Then A has extended both B and C

blocks|key|1671947|text|这不是真正的答案，我们有重复的类|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1671948|...but+it+works+:)|1671949|class+A+{
++++//do+some+things
}

class+B+{
++++//do+some+things
}|code-block|syntax|javascript|1671950|类copy_B复制所有类B|1671951|class+copy_B+extends+A+{

++++//do+some+things+(copy+class+B)
}

class+A_B+extends+copy_B{}|1671952|现在|1671953|class+C_A+extends+A{}
class+C_B+extends+B{}
class+C_A_b+extends+A_B{}++//extends+A+&+B|1671954|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|V|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|X|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

This is not a real answer, we have duplicate class 

...but it works :)

<pre><code>class A {
 //do some things
}

class B {
 //do some things
}
</code></pre>

class copy_B is copy all class B

<pre><code>class copy_B extends A {

 //do some things (copy class B)
}

class A_B extends copy_B{}
</code></pre>

now

<pre><code>class C_A extends A{}
class C_B extends B{}
class C_A_b extends A_B{} //extends A &amp; B
</code></pre>

If I have several classes with functions that I need but want to store separately for organisation, can I extend a class to have both?

i.e. <code>class a extends b extends c</code>

edit: I know how to extend classes one at a time, but I'm looking for a method to instantly extend a class using multiple base classes - AFAIK you can't do this in PHP but there should be ways around it without resorting to <code>class c extends b</code>, <code>class b extends a</code>

Can I extend a class using more than 1 class in PHP?

Java

如果我有几个具有所需函数的类，但又想单独存储以便于组织，我是否可以扩展一个类以同时拥有这两个类？即class a extends b extends c编辑:我知道如何一次扩展一个类，但我正在寻找一种方法，可以使用多个基类立即扩展一个类--你不能在PHP中做到这一点，但如果不求助于class c extends b，c...

问我可以在PHP中使用多个类来扩展一个类吗？
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问我可以在PHP中使用多个类来扩展一个类吗？
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