Page 268 - Beginning PHP 5.3

Part III: Using PHP in Practice
Capturing Form Data with PHP

You now know how to create an HTML form, and how data in a form is sent to the server. How do you
write a PHP script to handle that data when it arrives at the server?
First of all, the form ’ s action attribute needs to contain the URL of the PHP script that will handle the
form. For example:
< form action=”form_handler.php” method=”post” >

Next, of course, you need to create the form_handler.php script. When users send their forms, their
data is sent to the server and the form_handler.php script is run. The script then needs to read the
form data and act on it.
To read the data from a form, you use a few superglobal variables. You were introduced briefly to
superglobals in Chapter 7 . A superglobal is a built - in PHP variable that is available in any scope: at the
top level of your script, within a function, or within a class method. Chapter 7 discussed the $GLOBALS
superglobal array, which contains a list of all global variables used in your applications. Here, you learn
about three new superglobal arrays:

Superglobal Array Description

$_GET Contains a list of all the field names and values sent by a form using
the get method
$_POST Contains a list of all the field names and values sent by a form using
the post method
$_REQUEST Contains the values of both the $_GET and $_POST arrays combined,
along with the values of the $_COOKIE superglobal array

You learn about the $_COOKIE superglobal in the next chapter.

Each of these three superglobal arrays contains the field names from the sent form as array keys, with
the field values themselves as array values. For example, say you created a form using the get method,
and that form contained the following control:

< input type=”text ” name=”emailAddress” value=”” / >
You could then access the value that the user entered into that form field using either the $_GET or the
$_REQUEST superglobal:
$email = $_GET[“emailAddress”];

$email = $_REQUEST[“emailAddress”];

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