$_GET
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">
$_POST
$HTTP_POST_VARS [deprecated]
(No version information available, might be only in CVS)
$HTTP_POST_VARS [deprecated] — HTTP POST variables
Description
An associative array of variables passed to the current script via the HTTP POST method.
$HTTP_POST_VARS contains the same initial information, but is not a superglobal. (Note that $HTTP_POST_VARS and $_POST are different variables and that PHP handles them as such)
ChangeLog
| Version | Description |
|---|---|
| 4.1.0 | Introduced $_POST that deprecated $HTTP_POST_VARS. |
Examples
Example #1 $_POST example
<?php
echo 'Hello ' . htmlspecialchars($_POST["name"]) . '!';
?>
Assuming the user POSTed name=Hannes
The above example will output something similar to:
Hello Hannes!
Notes
Note: This is a 'superglobal', or automatic global, variable. This simply means that it is available in all scopes throughout a script. There is no need to do global $variable; to access it within functions or methods.
add a note
User Contributed Notes$_POST
php dot net at bigbadaboom dot net
15-Jul-2008 04:06
15-Jul-2008 04:06
paul dot chubb at abs dot gov dot au
19-Jun-2008 07:49
19-Jun-2008 07:49
Nasty bug in IE6, Apache2 and mod_auth_sspi. Essentially if the user presses the submit button too quickly, $_POST (and the equivalents) comes back empty. The workaround is to set Apache's KeepAliveTimeout to 1. This would mean that the user would need to push submit within a second to trigger the issue.
telconstar99 at hotnospampleasemail dot com
19-May-2008 08:49
19-May-2008 08:49
<?
//If we submitted the form
if(isset($_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>
<?
}
?>
