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HomeBackend DevelopmentPHP TutorialPHP5.3中新增的魔术常量DIR

我们知道PHP中提供了一个魔术常量( magic constant) __FILE__,用来指向当前执行的PHP脚本。

但PHP没有直接提供该脚本所在目录的常量。也就是说如果我们要得到当前PHP脚本所在的目录,需要使用dirname()这个函数:

$dir = dirname(__FILE__);

?>

在PHP5.3中,增加了一个新的常量__DIR__,指向当前执行的PHP脚本所在的目录。

例如当前执行的PHP文件为 /www/website/index.php

则 __FILE__等于' /www/website/index.php '

而 __DIR__等于' /www/website '

现在我们要包含当前文件目录或子目录下的文件,可以直接使用:

require_once __DIR__ . '/path/to/test.inc.php';?>

本文章为转载文章————原文地址    http://blog.csdn.net/haohappy2004/article/details/2114808

本文永久地址:http://blog.it985.com/15611.html

本文出自IT985博客 ,转载时请注明出处及相应链接。

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