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HomeBackend DevelopmentPHP TutorialPHP函数getenv简介和使用实例_php实例

getenv(PHP 4, PHP 5)

复制代码 代码如下:
// getenv — 获取一个环境变量的值

函数说明:
string getenv ( string $varname )

复制代码 代码如下:
// 获取一个环境变量的值。
// 使用 phpinfo() 你可以看到所有环境变量的列表。

参数说明:

复制代码 代码如下:
$varname 变量名。

函数返回值:

复制代码 代码如下:
// 返回环境变量 varname 的值, 如果环境变量 varname 不存在则返回 FALSE。

函数应用实例:

复制代码 代码如下:
// getenv() 使用示例
$ip = getenv('REMOTE_ADDR');

// 或简单仅使用全局变量($_SERVER 或 $_ENV)
$ip = $_SERVER['REMOTE_ADDR'];
?>

通过phpinfo可以看到整个PHP环境的配置信息,那么想要获取其中一个变量信息要咋办呢?
下面实际展示下,例如我要获取如下信息:

PHP函数getenv简介和使用实例_php实例

那么,PHP的源码是:

复制代码 代码如下:
echo getenv('userprofile');// C:\Windows\system32\config\systemprofile

很Easy吧?嘿~

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