Hello,
I'm working my way through O'Reilly's "Learning PHP 5", and I've hit a
brick wall. There are two files involved: the first contains some
helper functions to print HTML forms (form_helpers.php). The second
file (form_meals.php) calls these functions to print an HTML form with
various inputs.
The error I'm getting is "( ! ) Warning: Invalid argument supplied for
foreach() in form_helpers.php on line 80". This line is inside the
function input_select, specifically the foreach statement, which is
used to determine which elements are selected by default when the form
is displayed.
I think the error relates to the code that calls the input_select
function:
<?php input_select('main_dish', $defaults,
$GLOBALS['main_dishes'], $multiple = true) ?>
This program is taken directly from the ebook, so I cannot see why it
doesn't work.
Any pointers much appreciated.
Thanks
<?php
// form_helpers.php
//print a text box
function input_text($element_name, $values) {
print '<input type="text" name="' . $element_name .'" value="';
print htmlentities($values[$element_name]) . '">';
}
//print a submit button
function input_submit($element_name, $label) {
print '<input type="submit" name="' . $element_name .'" value="';
print htmlentities($label) .'"/>';
}
//print a textarea
function input_textarea($element_name, $values) {
print '<textarea name="' . $element_name .'">';
print htmlentities($values[$element_name]) . '</textarea>';
}
//print a radio button or checkbox
function input_radiocheck($type, $element_name, $values,
$element_value) {
print '<input type="' . $type . '" name="' . $element_name .'"
value="' . $element_value . '" ';
if ($element_value == $values[$element_name]) {
print ' checked="checked"';
}
print '/>';
}
//print a <select> menu
function input_select($element_name, $selected, $options, $multiple =
false) {
// print out the <select> tag
print '<select name="' . $element_name;
// if multiple choices are permitted, add the multiple attribute
// and add a [ ] to the end of the tag name
if ($multiple) { print '[]" multiple="multiple'; }
print '">';
// set up the list of things to be selected
$selected_options = array();
if ($multiple) {
foreach ($selected[$element_name] as $val) {
$selected_options[$val] = true;
}
} else {
$selected_options[ $selected[$element_name] ] = true;
}
// print out the <option> tags
foreach ($options as $option => $label) {
print '<option value="' . htmlentities($option) . '"';
if ($selected_options[$option]) {
print ' selected="selected"';
}
print '>' . htmlentities($label) . '</option>';
}
print '</select>';
}
?>
<?php
// form_meals.php
require ('form_helpers.php');
// don't forget to include the code for the form
// helper functions defined in Example 6-29
//
// setup the arrays of choices in the select menus
// these are needed in display_form(), validate_form(),
// and process_form(), so they are declared in the global scope
$sweets = array('puff' => 'Sesame Seed Puff',
'square' => 'Coconut Milk Gelatin Square',
'cake' => 'Brown Sugar Cake',
'ricemeat' => 'Sweet Rice and Meat');
$main_dishes = array('cuke' => 'Braised Sea Cucumber',
'stomach' => "Sauteed Pig's Stomach",
'tripe' => 'Sauteed Tripe with Wine Sauce',
'taro' => 'Stewed Pork with Taro',
'giblets' => 'Baked Giblets with Salt',
'abalone' => 'Abalone with Marrow and Duck
Feet');
// The main page logic:
// - If the form is submitted, validate and then process or redisplay
// - If it's not submitted, display
if ($_POST['_submit_check']) {
// If validate_form() returns errors, pass them to show_form()
if ($form_errors = validate_form()) {
show_form($form_errors);
} else {
// The submitted data is valid, so process it
process_form();
}
} else {
// The form wasn't submitted, so display
show_form();
}
function show_form($errors = '') {
// If the form is submitted, get defaults from submitted
parameters
if ($_POST['_submit_check']) {
$defaults = $_POST;
} else {
// Otherwise, set our own defaults: medium size and yes to
delivery
$defaults = array('delivery' => 'yes',
'size' => 'medium');
}
// If errors were passed in, put them in $error_text (with HTML
markup)
if ($errors) {
$error_text = '<tr><td>You need to correct the following
errors:';
$error_text .= '</td><td><ul><li>';
$error_text .= implode('</li><li>',$errors);
$error_text .= '</li></ul></td></tr>';
} else {
// No errors? Then $error_text is blank
$error_text = '';
}
// Jump out of PHP mode to make displaying all the HTML tags
easier
?>
<form method="POST" action="<?php print $_SERVER['PHP_SELF']; ?>">
<table>
<?php print $error_text ?>
<tr><td>Your Name:</td>
<td><?php input_text('name', $defaults) ?></td></tr>
<tr><td>Size:</td>
<td><?php input_radiocheck('radio','size', $defaults, 'small'); ?>
Small <br/>
<?php input_radiocheck('radio','size', $defaults, 'medium'); ?> Medium
<br/>
<?php input_radiocheck('radio','size', $defaults, 'large'); ?> Large
</td></tr>
<tr><td>Pick one sweet item:</td>
<td><?php input_select('sweet', $defaults, $GLOBALS['sweets']); ?>
</td></tr>
<tr><td>Pick two main dishes:</td>
<td>
<?php input_select('main_dish', $defaults, $GLOBALS['main_dishes'],
true) ?>
</td></tr>
<tr><td>Do you want your order delivered?</td>
<td><?php input_radiocheck('checkbox','delivery', $defaults, 'yes'); ?
> Yes
</td></tr>
<tr><td>Enter any special instructions.<br/>
If you want your order delivered, put your address here:</td>
<td><?php input_textarea('comments', $defaults); ?></td></tr>
<tr><td colspan="2" align="center"><?php
input_submit('save','Order'); ?>
</td></tr>
</table>
<input type="hidden" name="_submit_check" value="1"/>
</form>
<?php
} // The end of show_form()
function validate_form() {
$errors = array();
// name is required
if (! strlen(trim($_POST['name']))) {
$errors[] = 'Please enter your name.';
}
// size is required
if (($_POST['size'] != 'small') && ($_POST['size'] != 'medium') &&
($_POST['size'] != 'large')) {
$errors[] = 'Please select a size.';
}
// sweet is required
if (! array_key_exists($_POST['sweet'], $GLOBALS['sweets'])) {
$errors[] = 'Please select a valid sweet item.';
}
// exactly two main dishes required
if (count($_POST['main_dish']) != 2) {
$errors[] = 'Please select exactly two main dishes.';
} else {
// We know there are two main dishes selected, so make sure
they are
// both valid
if (! (array_key_exists($_POST['main_dish'][0],
$GLOBALS['main_dishes']) &&
array_key_exists($_POST['main_dish'][1],
$GLOBALS['main_dishes']))) {
$errors[] = 'Please select exactly two valid main
dishes.';
}
}
// if delivery is checked, then comments must contain something
if (($_POST['delivery'] == 'yes') && (!
strlen(trim($_POST['comments'])))) {
$errors[] = 'Please enter your address for delivery.';
}
return $errors;
}
function process_form() {
// look up the full names of the sweet and the main dishes in
// the $GLOBALS['sweets'] and $GLOBALS['main_dishes'] arrays
$sweet = $GLOBALS['sweets'][ $_POST['sweet'] ];
$main_dish_1 = $GLOBALS['main_dishes'][ $_POST['main_dish'][0] ];
$main_dish_2 = $GLOBALS['main_dishes'][ $_POST['main_dish'][1] ];
if ($_POST['delivery'] == 'yes') {
$delivery = 'do';
} else {
$delivery = 'do not';
}
// build up the text of the order message
$message=<<<_ORDER_
Thank you for your order, $_POST[name].
You requested the $_POST[size] size of $sweet, $main_dish_1, and
$main_dish_2.
You $delivery want delivery.
_ORDER_;
if (strlen(trim($_POST['comments']))) {
$message .= 'Your comments: '.$_POST['comments'];
}
// send the message to the chef
mail('chef@restaurant.example.com', 'New Order', $message);
// print the message, but encode any HTML entities
// and turn newlines into <br/> tags
print nl2br(htmlentities($message));
}
?>
Form helper issues "Invalid argument supplied for foreach()" 
Linear Mode
