预定义变量
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$_REQUEST

$_REQUEST — HTTP Request 变量

说明

默认情况下包含了 $_GET，$_POST 和 $_COOKIE 的数组。

更新日志

版本 说明
5.3.0 引入 request_order。该指令会影响 $_REQUEST 的内容。
4.3.0 $_FILES 信息被从 $_REQUEST 中移除。
4.1.0 引入 $_REQUEST。

注释

Note:

“Superglobal”也称为自动化的全局变量。 这就表示其在脚本的所有作用域中都是可用的。不需要在函数或方法中用 global $variable; 来访问它。

Note:

以命令行方式运行时，将不包含 argv 和 argc 信息；它们将存在于 $_SERVER 数组。

Note:

由于 $_REQUEST 中的变量通过 GET，POST 和 COOKIE 输入机制传递给脚本文件，因此可以被远程用户篡改而并不可信。这个数组的项目及其顺序依赖于 PHP 的 variables_order 指令的配置。

参见

预定义变量
在线手册：中文 英文
PHP手册
PHP手册 - N: HTTP Request 变量

用户评论:

rm at km-it dot de (23-Jan-2012 11:46)

Note that the default distribution php.ini files does not contain the 'C' for cookies, due to security concerns.
See http://http://php.net/manual/en/ini.core.php#ini.request-order

mike o. (12-Mar-2010 12:31)

The default php.ini on your system as of in PHP 5.3.0 may exclude cookies from $_REQUEST.  The request_order ini directive specifies what goes in the $_REQUEST array; if that does not exist, then the variables_order directive does.  Your distribution's php.ini may exclude cookies by default, so beware.

John Galt (07-Dec-2009 01:36)

I wrote a function because I found it inconvenient if I needed to change a particular parameter (get) while preserving the others. For example, I want to make a hyperlink on a web page with the URL http://www.example.com/script.php?id=1&blah=blah+blah&page=1 and change the value of "page" to 2 without getting rid of the other parameters.

<?php
 function add_or_change_parameter($parameter, $value)
 {
  $params = array();
  $output = "?";
  $firstRun = true;
  foreach($_GET as $key=>$val)
  {
   if($key != $parameter)
   {
    if(!$firstRun)
    {
     $output .= "&";
    }
    else
    {
     $firstRun = false;
    }
    $output .= $key."=".urlencode($val);
   }
  }
  if(!$firstRun)
   $output .= "&";
  $output .= $parameter."=".urlencode($value);
  return htmlentities($output);
 }
?>

Now, I can add a hyperlink to the page (http://www.example.com/script.php?id=1&blah=blah+blah&page=1) like this:
<a href="<?php echo add_or_change_parameter("page", "2"); ?>">Click to go to page 2</a>

The above code will output
<a href="?id=1&amp;blah=blah+blah&amp;page=2">Click to go to page 2</a>

Also, if I was setting "page" to a string rather than just "2", the value would be urlencode()'d.
<a href="<?php echo add_or_change_parameter("page", "banana+split!"); ?>">Click to go to page banana split!</a>
would become
<a href="?id=1&amp;blah=blah+blah&amp;page=banana+split%21">Click to go to page banana split!</a>

[EDIT BY danbrown AT php DOT net: Contains a bugfix provided by (theogony AT gmail DOT com), which adds missing `echo` instructions to the HREF tags.]

smjg at iname dot com (13-Aug-2009 11:56)

Selecting $_GET or $_POST depending on the request method isn't a general solution, since it's possible for an HTTP request to have both posted content and a query string in the URI.

If you want to allow for this possibility, you can use
<?php
$req = array_merge($_GET, $_POST);
?>
or vice versa, depending on which you want to be used in the event of a clash between them.

strata_ranger at hotmail dot com (17-Jul-2008 04:04)

Don't forget, because $_REQUEST is a different variable than $_GET and $_POST, it is treated as such in PHP -- modifying $_GET or $_POST elements at runtime will not affect the ellements in $_REQUEST, nor vice versa.

e.g:

<?php

$_GET['foo'] = 'a';
$_POST['bar'] = 'b';
var_dump($_GET); // Element 'foo' is string(1) "a"
var_dump($_POST); // Element 'bar' is string(1) "b"
var_dump($_REQUEST); // Does not contain elements 'foo' or 'bar'

?>

If you want to evaluate $_GET and $_POST variables by a single token without including $_COOKIE in the mix, use  $_SERVER['REQUEST_METHOD'] to identify the method used and set up a switch block accordingly, e.g:

<?php

switch($_SERVER['REQUEST_METHOD'])
{
case 'GET': $the_request = &$_GET; break;
case 'POST': $the_request = &$_POST; break;
.
. // Etc.
.
default:
}
?>