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PHP Integrating PHP with Databases Limiting Records in SQL Adding Pagination Links

Integrating PHP with Databases | Limiting Records in SQL | Adding Pagination Links

Hello PHP Experts!

I am having a hard time getting my Catalog page to work. Somehow, I've got some broken code that is causing some type of maybe endless loop behavior which causes the browser to return a redirect error: ERR_TOO_MANY_REDIRECTS.

What could I be doing wrong? Please have a look at the page code and let me know if you see anything I can modify to correct this behavior.

<?php 

include("inc/functions.php");


$pageTitle = "Full Catalog";
$section = null;
$items_per_page = 8;

if (isset($_GET["cat"])) {
    if ($_GET["cat"] == "books") {
        $pageTitle = "Books";
        $section = "books";
    } else if ($_GET["cat"] == "movies") {
        $pageTitle = "Movies";
        $section = "movies";
    } else if ($_GET["cat"] == "music") {
        $pageTitle = "Music";
        $section = "music";
    }
}
if (isset($_GET["pg"])) {
  $current_page = filter_input(INPUT_GET,"pg",FILTER_SANITIZE_NUMBER_INT);
}

if (empty($current_page)) {
  $current_page = 1;
}

$total_items = get_catalog_count($section);
$total_page = ceil($total_items / $items_per_page);

//limit results in redirect
$limit_results = "";
if (!empty($section)) {
  $limit_results = "cat=" . $section . "&";
}

//redirect too-large page numbers to the last page
if ($current_page > $total_pages) {
  header("location:catalog.php?pg="
         .$limit_results 
         . $total_pages);
}
//redirect too-small page numbers to the first page
if ($current_page < 1) {
  header("location:catalog.php?"
         . $limit_results
         . "pg=1");
}
//determine the offset (number of items to skip) for the current page
//for example, on page 3 with 8 items per page, the offset would be 16

$offset = ($current_page - 1) * $items_per_page;

if (empty($section)) {
  $catalog = full_catalog_array($items_per_page,$offset);
} else { 
  $catalog = category_catalog_array($section,$items_per_page,$offset);
}
$pagination = "<div class=\"pagination\">";
$pagination .= "Pages: ";  
for ($i = 1;$i <= $total_pages;$i++) {
    if ($i == $current_page) {
        $pagination .= " <span>$i</span>";
    } else {
        $pagination .= " <a href='catalog.php?";
        if (!empty($search)) {
            $pagination .= "s=".urlencode(htmlspecialchars($search))."&";
        } else if (!empty($section)) {
            $pagination .= "cat=".$section."&";
        }
        $pagination .= "pg=$i'>$i</a>";
    }
}
$pagination .= "</div>";

include("inc/header.php"); ?>

<div class="section catalog page">

    <div class="wrapper">

        <h1><?php 
        if ($section != null) {
            echo "<a href='catalog.php'>Full Catalog</a> &gt; ";
        }
        echo $pageTitle; ?></h1>
  <ul class="items">
            <?php
                foreach ($catalog as $item) {
                echo get_item_html($item);
            }
  ?>      
  </ul>

    </div>      

  </div>

<?php include("inc/footer.php"); ?>
Daniel Li
Daniel Li
15,244 Points

In short, the offending line is

$total_page = ceil($total_items / $items_per_page);

change it to

$total_pages = ceil($total_items / $items_per_page);

A tip to debug redirect loops is to first comment out the header call then echo the exact argument that goes inside the header function, that way you can inspect if there's anything wrong with the string or php throws out a notice if certain variables are not defined. Hope that is useful.