Databases: Finishing a Listing Service (
Page 1 of 5 )
Concluding our discussion of databases and PHP, we'll finish building the example that we started last week. This article is excerpted from chapter eight of the book Programming PHP, Second Edition, written by Kevin Tatroe, Rasmus Lerdorf, and Peter MacIntyre (O'Reilly, 2006; ISBN: 0596006810). Copyright © 2006 O'Reilly Media, Inc. All rights reserved. Used with permission from the publisher. Available from booksellers or direct from O'Reilly Media.
Administrator’s Page
Example 8-4 shows the backend page that allows administrators to add categories to the listing service. The input fields for adding a new record appear after a dump of the current data. The administrator fills in the form and presses the Add Category button, and the page redisplays with the new record. If any of the three fields are not filled in, the page displays an error message.
Example 8-4. Backend administration page
<html>
<head>
<?php
require_once('db_login.php');
?>
<title>
<?php
// print the window title and the topmost body heading
$doc_title = 'Category Administration';
echo "$doc_title\n";
?>
</title>
</head>
<body>
<h1>
<?php
echo "$doc_title\n";
?>
</h1>
<?php
// add category record input section
// extract values from $_REQUEST
$Cat_ID = $_REQUEST['Cat_ID'];
$Cat_Title = $_REQUEST['Cat_Title'];
$Cat_Desc = $_REQUEST['Cat_Desc'];
$add_record = $_REQUEST['add_record'];
// determine the length of each input field
$len_cat_id = strlen($_REQUEST['Cat_ID']);
$len_cat_tl = strlen($_REQUEST['Cat_Title']);
$len_cat_de = strlen($_REQUEST['Cat_Desc']);
// validate and insert if the form script has been
// called by the Add Category button
if ($add_record == 1) {
if (($len_cat_id > 0) and ($len_cat_tl > 0) and ($len_cat_de > 0)){
$sql = "insert into categories (category_id, title, description)";
$sql .= " values ('$Cat_ID', '$Cat_Title', '$Cat_Desc')";
$result = $db->query($sql);
$db->commit();
} else {
echo "<p>Please make sure all fields are filled in ";
echo "and try again.</p>\n";
}
}
// list categories reporting section
// query all records in the table after any
// insertion that may have occurred above
$sql = "select * from categories";
$result = $db->query($sql);
?>
<form method="post" action="<?= $PHP_SELF
?>">
<table>
<tr><th bgcolor="#eeeeee">Cat ID</th>
<th bgcolor="#eeeeee">Title</th>
<th bgcolor="#eeeeee">Description</th>
</tr>
<?php
// display any records fetched from the database
// plus an input line for a new category
while ($row = $result->fetchRow()){
echo "<tr><td>$row[0]</td><td>$row[1]</td><td>$row[2]</td></tr>\n";
}
?>
<tr><td><input type="text" name="Cat_ID" size="15" maxlength="10" /></td>
<td><input type="text" name="Cat_Title" size="40" maxlength="128" /></td>
<td><input type="text" name="Cat_Desc" size="45" maxlength="255" /></td>
</tr>
</table>
<input type="hidden" name="add_record" value="1" />
<input type="submit" name="submit" value="Add Category" />
</body>
</html>
When the administrator submits a new category, we construct a query to add the category to the database. Another query displays the table of all current categories. Figure 8-4 shows the page with five records loaded.
