php支持全局变量吗?
能否定义一个全局变量, 在不同的页面中赋予它不同的值然后调用。
比如定义 var=0
在a.php中
var=1;
include c.php
在b.php中
var=2;
include c.php
在c.php中判断
if(var==1)
include c1.php
if(var==2)
include c2.php
else
...
试着这么写过,貌似不可以。
把这个变量写入session是可以的。
------解决方案--------------------
不可以, PHP没有全局变量,可以用数据库或者文件保存读取
------解决方案--------------------
有全局变量
例如
$var = 0;写在 config.php内
c.php中 include_once('config.php');
然后就可以使用 $var变量
但是如果在函数当中想要使用$var
就要加上 global $var;
------解决方案--------------------
------解决方案--------------------
很多种的。session就是其中之一。
------解决方案--------------------
文字游戏?
global 全局的
凡是在函数和类之外的变量,都是全局变量
离开php程序单独存在的变量,php称之为系统变量。系统变量时只读的
$_GET、$_POST、$_SESSION 等为超全局变量
------解决方案--------------------
php里的session可以实现全局变量的设置,将值存入其中,有效,直到你删除它(cookie也有类似的做法)
------解决方案--------------------
在一个公用文件里面定义了,然后在所有文件中都包含这个文件,这个变量就算是全局变量了。。。
session ,数据库,隐藏域传值 这些也可以当全局变量 。
------解决方案--------------------
当然支持
------解决方案--------------------
将变量存入对象里面里面,类似php的单例模式,不就可以吗?我们可以去改变值,也可以全局调用。
------解决方案--------------------

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PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip

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PHP is suitable for web development and content management systems, and Python is suitable for data science, machine learning and automation scripts. 1.PHP performs well in building fast and scalable websites and applications and is commonly used in CMS such as WordPress. 2. Python has performed outstandingly in the fields of data science and machine learning, with rich libraries such as NumPy and TensorFlow.


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