Learn how to create a multipage form

This is identical to the earlier function, but we've snipped out the latter questions and changed the name of the next stage to cheese to more accurately describe what's next.

Now comes display_cheese().

<?php
function display_cheese() {
  global $PHP_SELF;
  global $name;

?>
<FORM TARGET="<?php echo $PHP_SELF; ?>" METHOD=GET>
Favorite Cheese: <INPUT TYPE=RADIO NAME="cheese" VALUE="brie">Very soft French Brie
                 <INPUT TYPE=RADIO NAME="cheese" VALUE="cheddar">Farmhouse English Cheddar
                 <INPUT TYPE=RADIO NAME="cheese" VALUE="mozzarella">Italian Buffalo Mozzarella

Favorite Times to Eat Cheese:                  <INPUT TYPE=CHECKBOX NAME="times[]" VALUE="m">Morning
                 <INPUT TYPE=CHECKBOX NAME="times[]" VALUE="n">Noon
                 <INPUT TYPE=CHECKBOX NAME="times[]" VALUE="d">Dinner
                 <INPUT TYPE=CHECKBOX NAME="times[]" VALUE="l">Late night

<INPUT TYPE=HIDDEN NAME="name" VALUE="<?php echo htmlspecialchars($name); ?>">
<INPUT TYPE=HIDDEN NAME="stage" VALUE="results">
<INPUT TYPE=SUBMIT VALUE="Thanks!">
</FORM>
<?php
}
?>

Again, the code above should look very familiar. We haven't made any unexpected modifications from before, except that right before we print the hidden stage element, we print the name and value of $name, our previous piece of data. We also don't just print the value directly, but run it through a PHP function called htmlspecialchars(). In HTML, there are four characters that aren't supposed to be used except as markup: <, >, ", and &. For that reason, in order to make sure we don't confuse the browser, we run $name through htmlspecialchars(), so someone whose name was formerly "Bret & Jeff" becomes "Brett & Jeff."

Now, when this new form is submitted, we won't lose any information.

As a result of this trick, we don't need to change one letter of process_form(). In fact, we'll even keep the name of the function the same. And, we'll need to add just one new line to our page-display logic.

<?php
if (empty($stage)) { display_name(); }
elseif ($stage == 'cheese') { display_cheese(); }
else { process_form(); }
?>

See that? All we did was sneak in an elseif in the middle of our two statements. That's the beauty of using $stage. If we want to add additional pages, we just need to write a new function to display what we want and a single line to control when it's displayed.

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