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php 析构方法 __destruct 什么情况下执行

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Release: 2016-06-06 20:35:49
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php 析构方法 __destruct 什么情况下执行
求所有的情况,是不是遇到?>php结束符也执行

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php 析构方法 __destruct 什么情况下执行
求所有的情况,是不是遇到?>php结束符也执行

RTFM

http://php.net/manual/en/language.oop5.decon.php#object.destruct

析构函数会在到某个对象的所有引用都被删除或者当对象被显式销毁时执行

在对象销毁前执行吧?

按照官方手册的描述,析构函数会在到某个对象的所有引用都被删除或者当对象被显式销毁时执行。代码演示如下

class sf
{
    public function __destruct()
    {
        echo __METHOD__ . PHP_EOL;
    }
}


$c1 = new sf;
$c2 = $c1;

echo 'unset $c2' . PHP_EOL;
unset($c2);

echo 'unset $c1' . PHP_EOL;
unset($c1);

// ----

$c1 = new sf;
$c2 = $c1;

echo 'null $c2' . PHP_EOL;
$c2 = null;

echo 'null $c1' . PHP_EOL;
$c1 = null;

// ----

$c1 = new sf;
$c2 = $c1;

echo '123 $c2' . PHP_EOL;
$c2 = 123;

echo '456 $c1' . PHP_EOL;
$c1 = 456;


echo 'the end' . PHP_EOL;
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运行结果如下

unset $c2
unset $c1
sf::__destruct
null $c2
null $c1
sf::__destruct
123 $c2
456 $c1
sf::__destruct
the end
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析构函数会在到某个对象的所有引用都被删除或者当对象被显式销毁时执行。

通常来说在脚本结束时(非unset)php才会销毁引用 在脚本结束运行之前运行。

原来遇到 exit();也执行了,蛋疼啊

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