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set_include_path

(PHP 4 >= 4.3.0, PHP 5)

set_include_path — Sets the include_path configuration option

说明

string set_include_path ( string $new_include_path )

Sets the include_path configuration option for the duration of the script.

参数

new_include_path

The new value for the include_path

返回值

Returns the old include_path on success 或者在失败时返回 FALSE.

范例

Example #1 set_include_path() example

<?php
// Works as of PHP 4.3.0
set_include_path('/usr/lib/pear');

// Works in all PHP versions
ini_set('include_path', '/usr/lib/pear');
?>

Example #2 Adding to the include path

Making use of the PATH_SEPARATOR constant, it is possible to extend the include path regardless of the operating system.

In this example we add /usr/lib/pear to the end of the existing include_path.

<?php
$path = '/usr/lib/pear';
set_include_path(get_include_path() . PATH_SEPARATOR . $path);
?>

参见

PHP 选项/信息 函数
在线手册：中文 英文
PHP手册
PHP手册 - N: Sets the include_path configuration option

用户评论:

cloxy at cloxy dot com (28-Mar-2012 02:11)

If you want to include files with their absolute path without changing the current include path, you can use the magic constant __DIR__ . For example:

<?php include(__DIR__.'/file.php'); ?>

It is available since PHP 5.3.

francois r vespa (01-Apr-2011 07:17)

include_path is not taking in consideration by very commonly used functions such as file_exists(), the following hack can come handy to override that

<?php

function suchFile($file)    // like file_exists() but takes in consideration include_path

{
    if(!file_exists($file))
   
    {
        $paths=explode(PATH_SEPARATOR,get_include_path());
       
        foreach($paths as $p)
        if(file_exists(preg_replace('%/$%','',$p)."/$file"))
        return true;
       
        return false;
    }
    else
    return true;
}
?>

joel at pittet dot ca (17-Nov-2010 10:46)

Seems set_include_path wasn't working for me.

The problem was i didn't have .:  in my include_path
Which seemed to stop the set_include_path().

mateusz at bkfmyjnie dot pl (14-May-2010 10:54)

It seems you can't really set empty inlude_path. First, set_include_path('') does exactly nothing (successfully), and second, '.' is always implicitly appended to the include path by PHP itself, as noted in comments below.

However, you can:
set_include_path(PATH_SEPARATOR); // note no quotes around the PATH_SEPARATOR; it's a string on its own

or, more explicit:
set_include_path('.');

Both seems to have the same result.

parks at vecinc dot com (27-Jul-2009 07:44)

If you find that this function is failing for you, and you're not sure why, you may have set your php include path in your sites's conf file in Apache  (this may be true of .htaccess as well)

So to get it to work, comment out any "php_value include_path" type lines in your Apache conf file, and you should be able to set it now in your php code.

ChanibaL.net (08-Jan-2009 01:21)

The files are included in order of the inclusion path, in this example, the directory structure is as follows:
.
|-- index.php
|-- t1
|   |-- a
|   `-- b
`-- t2
    |-- b
    `-- c

<?php

set_include_path('t1'.PATH_SEPARATOR.'t2');

include 'a';  // includes from T1
include 'b';  // includes from T1
include 'c';  // includes from T2

?>

Note that the include path affects only include/require functions.

<?php

var_dump(file_exists('a'));  // false
var_dump(fopen('b', 'r'));  // file not found

?>

ricardo dot ferro at gmail dot com (14-May-2008 07:16)

Two functions to help:

<?php

function add_include_path ($path)
{
    foreach (func_get_args() AS $path)
    {
        if (!file_exists($path) OR (file_exists($path) && filetype($path) !== 'dir'))
        {
            trigger_error("Include path '{$path}' not exists", E_USER_WARNING);
            continue;
        }
       
        $paths = explode(PATH_SEPARATOR, get_include_path());
       
        if (array_search($path, $paths) === false)
            array_push($paths, $path);
       
        set_include_path(implode(PATH_SEPARATOR, $paths));
    }
}

function remove_include_path ($path)
{
    foreach (func_get_args() AS $path)
    {
        $paths = explode(PATH_SEPARATOR, get_include_path());
       
        if (($k = array_search($path, $paths)) !== false)
            unset($paths[$k]);
        else
            continue;
       
        if (!count($paths))
        {
            trigger_error("Include path '{$path}' can not be removed because it is the only", E_USER_NOTICE);
            continue;
        }
       
        set_include_path(implode(PATH_SEPARATOR, $paths));
    }
}

?>

chris-r3i (06-Mar-2007 10:35)

Can be useful to check the value of the constant PATH_SEPARATOR.

<?php
if ( ! defined( "PATH_SEPARATOR" ) ) {
  if ( strpos( $_ENV[ "OS" ], "Win" ) !== false )
    define( "PATH_SEPARATOR", ";" );
  else define( "PATH_SEPARATOR", ":" );
}
?>

For older versions of php, PATH_SEPARATOR is not defined.
If it is so, we must check what kind of OS is on the web-server and define PATH_SEPARATOR properly

koenig at electronova dot net (02-Oct-2006 05:24)

You can also add several paths in one set_include_path separating them by ':'.
ex : set_include_path('/home/mysite/includes1:/home/mysite/includes2')

junya at xs4all dot nl (28-Jan-2005 01:41)

When you use .htaccess to set the include path, don't forget Apache directive 'AllowOverride Options' or 'AllowOverride All' is also needed.

df a t dougfelton d o t c o m (25-Jan-2005 03:37)

In order to use .htaccess files to set the include path, PHP must be installed as an Apache module. If PHP is compiled as a CGI binary, you can set the include path in a custom php.ini file (if, for example, you're being hosted somewhere and don't have access to the main php.ini file.  Note that custom php.ini files don't affect subdirectories in the way that .htaccess files do, so you'll need to put your custom php.ini file in any subdirectories as well.

r dot s dot goldsmith at far-blue dot co dot uk (08-Dec-2004 11:23)

If you want to set the paths php uses to find included files on a directory by directory level, you can do so in Apache's .htaccess file. Add the line:

php_value include_path  "<first path to look>:<second path>:<etc>:."

to the .htaccess file. This will replace any paths set in your environment or the php.ini file so remember to include the path to php's own libraries as, usually, the first option!

V.useful tip given to me by the 'php guy' at Edinburgh Uni's Computing Support.