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php如何注销global定义的全局变量

WBOY
Release： 2016-06-23 13:52:18
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最近看高性能php方面的东西，发现对于global的变量，在用完之后要注销掉，释放内存。

百度之后发现unregister_globals();  这个函数，但是不是太确定。

请大神指点一二~~


回复讨论(解决方案)

是谁这么无聊，让你做这怪异的事情？

这个很怪异么？

我理解错了。只要用unset()掉global的变量就可以了！！

你多半是在 函数里 global吧？ 函数跑完它就自动释放了...所以你什么也不需要做.
我估计你是跟$GLOBAL弄混了

你多半是在 函数里 global吧？ 函数跑完它就自动释放了...所以你什么也不需要做.
我估计你是跟$GLOBAL弄混了



代码是这样的
global  $db;
global $user;

unset($db,$user);

如果没有unset，$db,$user在函数结束时会被自动释放么？

global 只用在函数中声明全局变量的引用
请不要在函数外滥用，以免不必要的误会

php 在程序结束时将释放一切资源，当然包括变量

unset（）就可以啦

global 只用在函数中声明全局变量的引用
请不要在函数外滥用，以免不必要的误会

php 在程序结束时将释放一切资源，当然包括变量



原来如此，谢谢~
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