预定义变量
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$_POST

$HTTP_POST_VARS [已弃用]

$_POST -- $HTTP_POST_VARS [已弃用] — HTTP POST 变量

说明

通过 HTTP POST 方法传递给当前脚本的变量的数组。

$HTTP_POST_VARS 包含相同的信息，但它不是一个超全局变量。 (注意 $HTTP_POST_VARS 和 $_POST 是不同的变量，PHP 处理它们的方式不同)

更新日志

版本 说明
4.1.0 引入 $_POST，弃用 $HTTP_POST_VARS。

范例

Example #1 $_POST 范例

<?php
echo 'Hello ' . htmlspecialchars($_POST["name"]) . '!';
?>

假设用户通过 HTTP POST 方式传递了参数 name=Hannes

以上例程的输出类似于：

Hello Hannes!

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。

参见

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

用户评论:

perdondiego at mailinator dot com (24-May-2011 09:05)

In response to "php dot net at bigbadaboom dot net", adding the value attr to the image submit button may not work in older browser (Opera 9.x for example).

A better solution would be to add a hidden input (<input name="hidden" .... /> in the form to handle both cases: when we have a submit button or an image button for submitting

yesk13 at gmail dot com (22-Mar-2010 07:25)

you may have multidimensional array in form inputs

HTML Example:

<input name="data[User][firstname]" type="text" />
<input name="data[User][lastname]" type="text" />
...

Inside php script
after submit you can access the individual element like so:

$firstname = $_POST['data']['User']['firstname'];
...

toader_alexandru at yahoo dot com (29-Jan-2010 03:06)

When you have a form with some radio:
<?php
<form method='post'>
<input type='radio' name='55' value='1' >
<input type='radio' name='55' value='2' >
<input type='radio' name='55' value='3' >
<input type='radio' name='55' value='4' >

<input type='submit' value='ok' >
</form>

?>

if the name of the radio is a number will be returned by $_POST as INT!!!! not string as the manual says

if the name of the radio is 'test' will be of course returned ad string.

So your post array will look like this:
<?php
array
167302 => string '167308' (length=6)
167314 => string '167344' (length=6)
167347 => string '5867521' (length=7)
'3754952706' => string '3754952706' (length=10)
'3744466946' => string '3744466946' (length=10)
'3740271617' => string '3740271617' (length=10)
'3749709826' => string '3749709826' (length=10)
'3749708801' => string '1' (length=1)
'meta' =>
array
'hasJavascript' => string '0' (length=1)
'timeToComplete' => string '1264769572.6144' (length=15)
'Submit' => string 'Next' (length=4)

?>

Note the first 3 keys are int not string

This could affect you if you do some operations for example if you do an array_merge with your post values:

<?php
$arr1 = array(
167302 => '167308',
167314 => '167344',
167347 => '5867521',
'3754952706' => '3754952706',
'3744466946' => '3744466946',
'3740271617' => '3740271617',
'3749709826' => '3749709826',
'3749708801' => '1'
);

$arr2 = array(
'meta' =>
array (
'hasJavascript' => '0',
'timeToComplete' => '1264769572.6144'
)
);

?>

if you do :
<?php
$values = array_merge($arr1, $arr2);//this is done by zend in $form->getValues()
?>

guess what will be the result? your numeric keys will be reindexed starting from 0.

and your post values will look like this:

<?php

0 => string '167308' (length=6)
1 => string '167344' (length=6)
2 => string '5867521' (length=7)
'3754952706' => string '3754952706' (length=10)
'3744466946' => string '3744466946' (length=10)
'3740271617' => string '3740271617' (length=10)
'3749709826' => string '3749709826' (length=10)
'3749708801' => string '1' (length=1)
'meta' =>
array
'hasJavascript' => string '0' (length=1)
'timeToComplete' => string '1264769572.6144' (length=15)

?>

eddyvlad at eddyvlad dot com (25-Mar-2009 03:34)

Take note that all $_POST values are (string).
If your form field should accept both numeric and alphabets but exclude a value of 0, you will have a problem.

<?php
## Using Equal operator
if($_POST['myfield'] == 0){
    echo 'You cannot set it to 0';
} else {
    echo 'Correct';
}
# You will get the following results

// $_POST['myfield'] = 0;
// Output: You cannot set it to 0;

// $_POST['myfield'] = 1;
// Output: Correct;

// $_POST['myfield'] = 'test';
// Output: You cannot set it to 0;

## Using Identical operator
if($_POST['myfield'] === 0){
    echo 'You cannot set it to 0';
} else {
    echo 'Correct';
}
# You will get the following results

// $_POST['myfield'] = 0;
// Output: Correct;

// $_POST['myfield'] = 1;
// Output: Correct;

// $_POST['myfield'] = 'test';
// Output: Correct;

// You need to convert numeric values to integer and use identical operator
$_POST['myfield'] = is_numeric($_POST['myfield']) ? (int)$_POST['myfield'] : $_POST['alias'];
if($_POST['myfield'] === 0){
    echo 'You cannot set it to 0';
} else {
    echo 'Correct';
}
# Now you will get the following results

// $_POST['myfield'] = 0;
// Output: You cannot set it to 0;

// $_POST['myfield'] = 1;
// Output: Correct;

// $_POST['myfield'] = 'test';
// Output: Correct;
?>

initself (23-Jan-2009 07:08)

# This will convert $_POST into a query string

<?php
$query_string = "";
if ($_POST) {
  $kv = array();
  foreach ($_POST as $key => $value) {
    $kv[] = "$key=$value";
  }
  $query_string = join("&", $kv);
}
else {
  $query_string = $_SERVER['QUERY_STRING'];
}
echo $query_string;
?>

james dot ellis at gmail dot com (15-Dec-2008 01:38)

One feature of PHP's processing of POST and GET variables is that it automatically decodes indexed form variable names.

I've seem innumerable projects that jump through extra & un-needed processing hoops to decode variables when PHP does it all for you:

Example pseudo code:

Many web sites do this:

<form ....>
<input name="person_0_first_name" value="john" />
<input name="person_0_last_name" value="smith" />
...

<input name="person_1_first_name" value="jane" />
<input name="person_1_last_name" value="jones" />
</form>

When they could do this:

<form ....>
<input name="person[0][first_name]" value="john" />
<input name="person[0][last_name]" value="smith" />
...
<input name="person[1][first_name]" value="jane" />
<input name="person[1][last_name]" value="jones" />
</form>

With the first example you'd have to do string parsing / regexes to get the correct values out so they can be married with other data in your app... whereas with the second example.. you will end up with something like:
<?php
var_dump($_POST['person']);
//will get you something like:
array (
0 => array('first_name'=>'john','last_name'=>'smith'),
1 => array('first_name'=>'jane','last_name'=>'jones'),
)
?>

This is invaluable when you want to link various posted form data to other hashes on the server side, when you need to store posted data in separate "compartment" arrays or when you want to link your POSTed data into different record handlers in various Frameworks.

Remember also that using [] as in index will cause a sequential numeric array to be created once the data is posted, so sometimes it's better to define your indexes explicitly.

paul at youngish dot homelinux^org (08-Dec-2008 09:09)

For a page with multiple forms here is one way of processing the different POST values that you may receive.  This code is good for when you have distinct forms on a page.  Adding another form only requires an extra entry in the array and switch statements.

<?php

 if (!empty($_POST))
 {
    // Array of post values for each different form on your page.
    $postNameArr = array('F1_Submit', 'F2_Submit', 'F3_Submit');       

    // Find all of the post identifiers within $_POST
    $postIdentifierArr = array();
       
    foreach ($postNameArr as $postName)
    {
        if (array_key_exists($postName, $_POST))
        {
             $postIdentifierArr[] = $postName;
        }
    }

    // Only one form should be submitted at a time so we should have one
    // post identifier.  The die statements here are pretty harsh you may consider
    // a warning rather than this.
    if (count($postIdentifierArr) != 1)
    {
        count($postIdentifierArr) < 1 or
            die("\$_POST contained more than one post identifier: " .
               implode(" ", $postIdentifierArr));

        // We have not died yet so we must have less than one.
        die("\$_POST did not contain a known post identifier.");
    }
        
    switch ($postIdentifierArr[0])
    {
    case 'F1_Submit':
       echo "Perform actual code for F1_Submit.";
       break;

    case 'Modify':
       echo "Perform actual code for F2_Submit.";
       break;
          
    case 'Delete':
       echo "Perform actual code for F3_Submit.";
       break;
    }
}
else // $_POST is empty.
{
    echo "Perform code for page without POST data. ";
}
?>

jairhumberto at gmail dot com (31-Jul-2008 02:26)

<?php

foreach($_POST as $k=>$v) $$k=$v;
//to use $_POST["example"] as $example

foreach($_GET as $k=>$v) $$k=$v;
//to use $_GET["example"] as $example

//or better:

foreach(${"_" . $_SERVER["REQUEST_METHOD"]} as $k=>$v) $$k=$v;
//to use $_GET["example"] or $_POST["example"] as $example

?>

php dot net at bigbadaboom dot net (15-Jul-2008 09:06)

Make sure your submit buttons (ie. <input type="submit"> etc) have a 'value' attribute.  If they don't, the value won't appear in $_POST and so isset($_POST["submit"]) won't work either.

Example:

<input type="submit" name="submit">

isset($_POST["submit"]) returns false

<input type="submit" name="submit" value="Next">

isset($_POST["submit"]) returns true.

This might seem obvious for text buttons since they need a label anyway.  However, if you are using image buttons, it might not occur to you that you need to set a value attribute as well.  For example, the value attribute is required in the following element if you want to be able to detect it in your script.

<input type="image" name="submit" src="next.gif" value="Next">

paul dot chubb at abs dot gov dot au (20-Jun-2008 12:49)

Nasty bug in IE6, Apache2 and mod_auth_sspi. Essentially if the user presses the submit button too quickly, $_POST (and the equivalents) comes back empty. The workaround is to set Apache's KeepAliveTimeout to 1. This would mean that the user would need to push submit within a second to trigger the issue.

telconstar99 at hotnospampleasemail dot com (20-May-2008 01:49)

<?
//If we submitted the form
if(isset($_POST['submitMe']))
{
     echo("Hello, " . $_POST['name'] . ", we submitted your form!");
}
//If we haven't submitted the form
else
{
?>
    <form action="<?=$_SERVER['PHP_SELF']?>" method="POST">
    <input type="text" name="name"><br>
    <input type="submit" value="submit" name="submitMe">
    </form>
<?
}
?>