php static
php static oop
RT,用CI框架在写一个php网页,现发现static关键字不太会用,简化代码如下:class A extends CI_Controller{ private static $num = 0; public function f1(){ self::$num = 1; this->load->view('v1'); } public function f2(){ if(self::$num === 1){ this->load->view('v2'); }else{ this->load->view('v3'); } }}
刚开始我们访问函数f1,在f1中跳转到页面v1,然后在v1中又跳回f2,但是此时的num已经被重置了,会跳转到v3,这是为什么呢?php中的static不彻底吗?
回复讨论(解决方案)
"然后在v1中又跳回f2"
你是怎么跳的?
如果是在 v1 中由实例化了 A ,那么 num 当然要被重置
我感觉你需要的是“单例模式”的 A
"然后在v1中又跳回f2"
你是怎么跳的?
如果是在 v1 中由实例化了 A ,那么 num 当然要被重置
我感觉你需要的是“单例模式”的 A
先不说单利模式,v1中往回跳很简单啊,就是一个链接,www.xxxx.com/index.php/A/f2,这样就跳回来了
那你就在开玩笑了!你从url进入,还能回到原来的现场吗?
那你就在开玩笑了!你从url进入,还能回到原来的现场吗?
啊?好吧……我是凭直觉这么想的。。
我认为这个class在载入内存之时就有num这个变量,而且因为它是static的,所以不会因为页面跳转引发的对象消亡而被释放,所以在再次进入之时,num还应该是对象消亡之前的样子。

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