exit

    (PHP 4, PHP 5, PHP 7, PHP 8)

    exit — 使用状态 code 或消息终止当前脚本

    说明

    exit(string|int $status = 0): never

    中止脚本的执行。即使调用了 exit()，Shutdown 函数 以及 对象析构方法 始终会执行。但 finally 块永远不会执行。

    退出 code 0 表示程序已成功完成任务。其它任何值都表示执行过程中发生了某种错误。

    exit() 是特殊函数，因为在解析器中有个专用记号，因此可以像语句一样使用（即没有括号），以使用默认状态 code 终止脚本。

    警告

    无法禁用或创建命名空间函数来屏蔽全局 exit() 函数。

    参数

    status
    如果 status 是字符串，此函数将在退出前打印 status。PHP 返回的退出 code 为 0。

    如果 status 是 int，PHP 返回的退出 code 将为 status。

    注意: 退出 code 的范围应在 0 到 254 内，退出 code 255 由 PHP 保留，不应使用。

    警告

    PHP 8.4.0 之前，exit() 不遵循 PHP 的标准类型处理语义，也不遵守 strict_types 声明。

    任何非 int 类型的值（包括 resource 和 array 值）均会转换为 string。自 PHP 8.4.0 起，遵循通用的类型处理语义，并在无效值上抛出 TypeError。

    返回值

    由于这会终止 PHP 脚本，因此没有返回任何值。

    更新日志

    版本 说明
    8.4.0 exit() 现在是真正的函数，因此遵循通用的类型处理语义，受 strict_types 声明的影响，可以用命名参数调用，并且是变量函数。

    示例

    示例 #1 基础 exit() 示例

    <?php

    // 正常退出程序
    exit();
    exit(    0);

    // 带着错误 code 的退出
    exit(1);

    ?>

    示例 #2 exit() 的 string 示例

    <?php

    $filename     = '/path/to/data-file';
    $file = fopen($filename, 'r')
    or exit(    "unable to open file ($filename)");

    ?>

    示例 #3 Shutdown 函数和析构方法无论如何都会运行

    <?php
    class Foo
    {
    public function     __destruct()
    {
    echo     'Destruct: ' . __METHOD__ . '()' . PHP_EOL;
    }
    }

    function     shutdown()
    {
    echo     'Shutdown: ' . __FUNCTION__ . '()' . PHP_EOL;
    }

    $foo = new Foo();
    register_shutdown_function('shutdown');

    exit();
    echo     'This will not be output.';
    ?>

    以上示例会输出：

    Shutdown: shutdown()
Destruct: Foo::__destruct()

    示例 #4 exit() 作为语句

    <?php

    // 程序正常退出，退出 code 为 0
    exit;

    ?>

    注释

    警告

    PHP 8.4.0 之前，exit() 是语言结构而不是函数，因此无法使用变量函数或命名参数调用。

    参见

    发现了问题？

    了解如何改进此页面 • 提交拉取请求 • 报告一个错误
    ＋添加备注

    用户贡献的备注 14 notes

    up
    38
    dexen dot devries at gmail dot com
    14 years ago
    If you want to avoid calling exit() in FastCGI as per the comments below, but really, positively want to exit cleanly from nested function call or include, consider doing it the Python way:

    define an exception named `SystemExit', throw it instead of calling exit() and catch it in index.php with an empty handler to finish script execution cleanly.

    <?php

    // file: index.php
    class SystemExit extends Exception {}
    try {
    /* code code */
    }
    catch (    SystemExit $e) { /* do nothing */ }
    // end of file: index.php

    // some deeply nested function or .php file

    if (SOME_EXIT_CONDITION)
    throw new     SystemExit(); // instead of exit()

    ?>
    up
    35
    albert at removethis dot peschar dot net
    15 years ago
    jbezorg at gmail proposed the following:

    <?php

    if($_SERVER['SCRIPT_FILENAME'] == __FILE__ )
    header('Location: /');

    ?>

    After sending the `Location:' header PHP _will_ continue parsing, and all code below the header() call will still be executed. So instead use:

    <?php

    if($_SERVER['SCRIPT_FILENAME'] == __FILE__)
    {
    header('Location: /');
    exit;
    }

    ?>
    up
    18
    theonenkl at gmail dot com
    9 years ago
    A side-note for the use of exit with finally: if you exit somewhere in a try block, the finally won't be executed. Could not sound obvious: for instance in Java you never issue an exit, at least a return in your controller; in PHP instead you could find yourself exiting from a controller method (e.g. in case you issue a redirect).

    Here follows the POC:

    <?php
    echo "testing finally wit exit\n";

    try {
    echo     "In try, exiting\n";

    exit;
    } catch(    Exception $e) {
    echo     "catched\n";
    } finally {
    echo     "in finally\n";
    }

    echo     "In the end\n";
    ?>

    This will print:

    testing finally wit exit
    In try, exiting
    up
    2
    tianyiw at vip dot qq dot com
    2 years ago
    These are the standard error codes in Linux or UNIX.

    1 - Catchall for general errors
    2 - Misuse of shell builtins (according to Bash documentation)
    126 - Command invoked cannot execute
    127 - “command not found”
    128 - Invalid argument to exit
    128+n - Fatal error signal “n”
    130 - Script terminated by Control-C
    255\* - Exit status out of range
    up
    11
    vincent dot laag at gmail dot com
    14 years ago
    Don't use the exit() function in the auto prepend file with fastcgi (linux/bsd os).
    It has the effect of leaving opened files with for result at least a nice "Too many open files ..." error.
    up
    3
    chris at ocproducts dot com
    6 years ago
    Calling 'exit' will bypass the auto_append_file option.
    On some free hosting this risks you getting removed, as they may be using for ads and analytics.

    So be a bit careful if using this on the most common output branch.
    up
    5
    emils at tvnet dot lv
    21 years ago
    Note, that using exit() will explicitly cause Roxen webserver to die, if PHP is used as Roxen SAPI module. There is no known workaround for that, except not to use exit(). CGI versions of PHP are not affected.
    up
    8
    void a t informance d o t info
    16 years ago
    To rich dot lovely at klikzltd dot co dot uk:

    Using a "@" before header() to suppress its error, and relying on the "headers already sent" error seems to me a very bad idea while building any serious website.

    This is *not* a clean way to prevent a file from being called directly. At least this is not a secure method, as you rely on the presence of an exception sent by the parser at runtime.

    I recommend using a more common way as defining a constant or assigning a variable with any value, and checking for its presence in the included script, like:

    in index.php:
    <?php
    define     ('INDEX', true);
    ?>

    in your included file:
    <?php
    if (!defined('INDEX')) {
    die(    'You cannot call this script directly !');
    }
    ?>

    BR.

    Ninj
    up
    4
    m dot libergolis at gmail dot com
    9 years ago
    In addition to "void a t informance d o t info", here's a one-liner that requires no constant:

    <?php basename($_SERVER['PHP_SELF']) == basename(__FILE__) && die('Thou shall not pass!'); ?>

    Placing it at the beginning of a PHP file will prevent direct access to the script.

    To redirect to / instead of dying:

    <?php
    if (basename($_SERVER['PHP_SELF']) == basename(__FILE__)) {
    if (    ob_get_contents()) ob_clean(); // ob_get_contents() even works without active output buffering
    header('Location: /');
    die;
    }
    ?>

    Doing the same in a one-liner:

    <?php basename($_SERVER['PHP_SELF']) == basename(__FILE__) && (!ob_get_contents() || ob_clean()) && header('Location: /') && die; ?>

    A note to security: Even though $_SERVER['PHP_SELF'] comes from the user, it's safe to assume its validity, as the "manipulation" takes place _before_ the actual file execution, meaning that the string _must_ have been valid enough to execute the file. Also, basename() is binary safe, so you can safely rely on this function.
    up
    2
    jean dot claveau at gmail dot com
    5 years ago
    Beware if you enabled uopz extension, it disables exit / die() by default. They are just "skipped".

    https://www.php.net/manual/en/function.uopz-allow-exit.php
    up
    3
    alexyam at live dot com
    12 years ago
    When using php-fpm, fastcgi_finish_request() should be used instead of register_shutdown_function() and exit()

    For example, under nginx and php-fpm 5.3+, this will make browsers wait 10 seconds to show output:

    <?php
    echo "You have to wait 10 seconds to see this.<br>";
    register_shutdown_function('shutdown');
    exit;
    function     shutdown(){
    sleep(10);
    echo     "Because exit() doesn't terminate php-fpm calls immediately.<br>";
    }
    ?>

    This doesn't:

    <?php
    echo "You can see this from the browser immediately.<br>";
    fastcgi_finish_request();
    sleep(10);
    echo     "You can't see this form the browser.";
    ?>
    up
    3
    devinemke at devinemke dot com
    23 years ago
    If you are using templates with numerous includes then exit() will end you script and your template will not complete (no </table>, </body>, </html> etc...). Rather than having complex nested conditional logic within your content, just create a "footer.php" file that closes all of your HTML and if you want to exit out of a script just include() the footer before you exit().

    for example:

    include ('header.php');
    blah blah blah
    if (!$mysql_connect) {
    echo "unable to connect";
    include ('footer.php');
    exit;
    }
    blah blah blah
    include ('footer.php');
    up
    0
    bill dot gates at hotmail dot com
    3 years ago
    Be noticed about uopz (User Operations for Zend) extension of PHP. It disables (prevents) halting of PHP scripts (both FPM and CLI) on calling `exit()` and `die()` by default just after enabling the extension. Therefore your script will continue to execute.

    Details: https://www.php.net/manual/en/uopz.configuration.php#ini.uopz.exit
    up
    0
    sunfundev at gmail dot com
    7 years ago
    >> Shutdown functions and object destructors will always be executed even if exit is called.

    It is false if you call exit into desctructor.

    Normal exit:
    <?php
    class A
    {
    public function     __destruct()
    {
    echo     "bye A\n";
    }
    }

    class     B
    {
    public function     __destruct()
    {
    echo     "bye B\n";
    }
    }

    $a = new A;
    $b = new B;
    exit;

    // Output:
    // bye B
    // bye A
    ?>

    // Exit into desctructor:
    <?php
    class A
    {
    public function     __destruct()
    {
    echo     "bye A\n";
    }
    }

    class     B
    {
    public function     __destruct()
    {
    echo     "bye B\n";
    exit;
    }
    }

    $a = new A;
    $b = new B;

    // Output:
    // bye B
    ?>
    ＋添加备注
    To Top