怎样可以在全局中使用局部变量
第19行中的$y是未定义的 有什么方法可以把第5行的局部变量可以在全局使用
问这个问题的原因是我才开始学PHP想知道是否有这样的方法 谢谢
回复内容:
怎样可以在全局中使用局部变量
第19行中的$y是未定义的 有什么方法可以把第5行的局部变量可以在全局使用
问这个问题的原因是我才开始学PHP想知道是否有这样的方法 谢谢
global $y;
$y = 10;
global $adfds=&y;
<code>你试试这个,我蒙的;</code>
有两种方法 一个是加 global 关键字,global $y; $y =10; 第二个是放在超全局数组$GLOBALS中,如$GLOBALS['y'] =10
如果是先有全局变量$a, 然后在局部作用域引用它,用global关键字声明即可。
(函数里面如果用$a的话默认会重新创建一个局部的$a而不是用全局的)。
这个是官方的关于global的页面:(建议碰到问题先看下官方的手册)
http://www.php.net/manual/zh/language.va...
可是你的问题是,函数里有个局部变量$y,怎么把它变成全局的?
答案是,没有办法。。。。php没这个功能。。。=_=
放心吧,平常你是用不着这么搞的。平常写程序即使是global关键字也很少很少用到。

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