Page 267 - Beginning PHP 5.3

Chapter 9: Handling HTML Forms with PHP
Try filling in a few of the fields, then clicking the Submit Form button. Because the action attribute in
the <form> tag is an empty string, the browser sends the form data back to the same URL (web_form.
html). Obviously web_form.html can’t do anything with the form data because it’s simply an HTML
Web page, but shortly you’ll be writing PHP scripts that can handle data sent from a form.

Notice that, once you submit your form, you can see all of the form data in your browser’s address bar,
as shown in Figure 9-2. This is because your form used the get method, which sends the form data in
the URL. You can see that the form data is preceded by a ? character, and that the data for each form
field is sent as a name/value pair:
http://localhost/web_form.html?textField=Hello&passwordField=secret& ...
The get method is limited in the amount of data it can send, because a URL can only contain a small
number of characters (1,024 characters is a safe upper limit). If you need to send larger amounts of data
from a form, use the post method instead:

<form action=”myscript.php” method=”post”>
The post method sends the data within the HTTP headers of the request that’s sent to the server, rather
than embedding the data in the URL. This allows a lot more data to be sent. If the users try to refresh the
page after sending a form via the post method, their browser usually pops up a dialog box asking them
if they want to resend their form data.
You can find out more about HTTP headers in Chapter 16.

Figure 9-2

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