4.3. Gathering Information from the User with Forms (The definitive guide of Symfony 1.0)

Forms are a good way to get information from the user. Writing form and form elements in HTML can sometimes be cumbersome, especially when you want to be XHTML-compliant. You could include form elements in symfony templates the usual way, as shown in Listing 4-8, but symfony provides helpers that make this task easier.

Listing 4-8 - Templates Can Include Usual HTML Code

<p>Hello, world!</p>
<?php if ($hour >= 18): ?>
<p>Or should I say good evening? It is already <?php echo $hour ?>.</p>
<?php endif; ?>
<form method="post" action="/myapp_dev.php/mymodule/anotherAction">
  <label for="name">What is your name?</label>
  <input type="text" name="name" id="name" value="" />
  <input type="submit" value="Ok" />
</form>

A helper is a PHP function defined by symfony that is meant to be used within templates. It outputs some HTML code and is faster to use than writing the actual HTML code by yourself. Using symfony helpers, you can have the same result as in Listing 4-8 with the code shown in Listing 4-9.

Listing 4-9 - It Is Faster and Easier to Use Helpers Than to Use HTML Tags

<p>Hello, world!</p>
<?php if ($hour >= 18): ?>
<p>Or should I say good evening? It is already <?php echo $hour ?>.</p>
<?php endif; ?>
<?php echo form_tag('mymodule/anotherAction') ?>
  <?php echo label_for('name', 'What is your name?') ?>
  <?php echo input_tag('name') ?>
  <?php echo submit_tag('Ok') ?>
</form>

Helpers are here to help you If, in the example in Listing 4-9, you think the helper version is not really faster to write than the HTML one, consider this one:

<?php
 $card_list = array(
   'VISA' => 'Visa',
   'MAST' => 'MasterCard',
   'AMEX' => 'American Express',
   'DISC' => 'Discover');
 echo select_tag('cc_type', options_for_select($card_list, 'AMEX'));
 ?>

This outputs the following HTML:

<select name="cc_type" id="cc_type">
    <option value="VISA">Visa</option>
    <option value="MAST">MasterCard</option>
    <option value="AMEX" selected="selected">American Express</option>
    <option value="DISC">Discover</option>
</select>

The benefit of helpers in templates is raw speed of coding, clarity of code, and concision. The only price to pay is the time to learn them, which will end when you finish this book, and the time to write , for which you should already have a shortcut in your favorite text editor. So you could not use the symfony helpers in templates and write HTML the way you always did, but this would be a great loss and much less fun.

Note that the use of the short opening tags (<?=, equivalent to <?php echo) is not recommended for professional web applications, since your production web server may be able to understand more than one scripting language and consequently get confused. Besides, the short opening tags do not work with the default PHP configuration and need server tweaking to be activated. Ultimately, when you have to deal with XML and validation, it falls short because <? has a special meaning in XML.

Form manipulation deserves a whole chapter of its own, since symfony provides many tools, mostly helpers, to make it easier. You will learn more about these helpers in Chapter 10.