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请教有没有人用过traits类型?有个有关问题需要问

WBOY
WBOYOriginal
2016-06-13 12:54:371111browse

请问有没有人用过traits类型?有个问题需要问

<br />
<?php<br />
	trait Counter {<br />
		static $a = 5;<br />
		public function inc() {<br />
			static $c = 0;<br />
			$c += 1;<br />
			echo "$c<br />";<br />
		}<br />
	}<br />
	<br />
	class C1 {<br />
		use Counter;<br />
	}<br />
	<br />
	class C2 {<br />
		use Counter;<br />
	}<br />
	<br />
	<br />
	<br />
	$o = new C1();<br />
	$o->inc();<br />
	echo Counter::$a;<br />
	echo '<br />';<br />
	<br />
	$p = new C2();<br />
	$p->inc();<br />
?><br />


手册上讲“静态变量可以被 trait 的方法引用,但不能被 trait 定义。但是 traits 能够为使用的类定义静态方法”,但为什么我这个例子中的static $a = 5;又可以成功定义并最后成功输出?

class function php
------解决方案--------------------
trait 是 php 5.4 才加入的
你的手册是最新的吗?
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