PHP: paging with Ajax not working correctly - php

Question

I'm fetching records from a database and displaying them in gruops using php and ajax.
The script below (found somewhere) is almost working, but it seems that when you are on the first page and clicking "Next" you are taken to the LAST page.
Only when clicking the numbers individually, the paging is correct.
I can provide a test link in a PM if needed.
index.php:
<script>
$(document).ready(function() {
$("#results" ).load( "pages.php"); //load initial records
//executes code below when user click on pagination links
$("#results").on( "click", ".pagination a", function (e){
e.preventDefault();
var page = $(this).attr("data-page"); //get page number from link
$("#results").load("pages.php",{"page":page}, function(){ //get content from PHP page
});
});
});
</script>
<div id="results"></div>
pages.php:
<?php
// continue only if $_POST is set and it is a Ajax request
if (isset($_POST) && isset($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest') {
include (realpath(__DIR__ . '/../db.php'));
// Get page number from Ajax POST
if (isset($_POST["page"])) {
$page_number = filter_var($_POST["page"], FILTER_SANITIZE_NUMBER_INT, FILTER_FLAG_STRIP_HIGH); //filter number
if (!is_numeric($page_number)) {
die('Invalid page number!');
}
}
else {
$page_number = 1; //if there's no page number, set it to 1
}
// get total number of records from database for pagination
$sql = "SELECT * FROM " . $DBtable . " ORDER BY dates DESC";
$rs = $conn->query($sql);
if ($rs === false) {
trigger_error('Wrong SQL: ' . $sql . ' Error: ' . $conn->error, E_USER_ERROR);
}
else {
$get_total_rows = $rs->fetch_row(); //hold total records in variable
}
// break records into pages
$total_pages = ceil($get_total_rows[0] / $item_per_page);
// get starting position to fetch the records
$page_position = (($page_number - 1) * $item_per_page);
// Limit our results within a specified range.
$rs = $conn->prepare("SELECT id, title, description, dates, clicks FROM " . $DBtable . " ORDER BY dates DESC LIMIT $page_position, $item_per_page");
$rs->execute(); //Execute prepared Query
$rs->bind_result($id, $title, $description, $dates, $clicks); //bind variables to prepared statement
echo '<ul class="contents">';
while($rs->fetch()){ //fetch values
echo '<li>';
echo $id. '. <strong>' .$name.'</strong> — '.$description;
echo '</li>';
}
echo '</ul>';
echo '<div align="center">';
/* We call the pagination function here to generate Pagination link for us. */
echo paginate_function($item_per_page, $page_number, $get_total_rows[0], $total_pages);
echo '</div>';
exit;
}
// ############### pagination function #########################################
function paginate_function($item_per_page, $current_page, $total_records, $total_pages) {
$pagination = '';
if ($total_pages > 0 && $total_pages != 1 && $current_page <= $total_pages) { //verify total pages and current page number
$pagination.= '<ul class="pagination">';
$right_links = $current_page + 3;
$previous = $current_page - 3; //previous link
$next = $current_page + 1; //next link
$first_link = true; //boolean var to decide our first link
if ($current_page > 1) {
$previous_link = ($previous == 0) ? 1 : $previous;
$pagination.= '<li class="class="page-item" first"><a class="page-link" href="#" data-page="1" title="First">«</a></li>'; //first link
$pagination.= '<li class="page-item"><a class="page-link" href="#" data-page="' . $previous_link . '" title="Prev"><</a></li>'; //previous link
for ($i = ($current_page - 2); $i < $current_page; $i++) { //Create left-hand side links
if ($i > 0) {
$pagination.= '<li class="page-item"><a class="page-link" href="#" data-page="' . $i . '" title="Page' . $i . '">' . $i . '</a></li>';
}
}
//set first link to false
$first_link = false;
}
if ($first_link) { //if current active page is first link
$pagination.= '<li class="page-item active first"><a class="page-link" href="#">' . $current_page . '<span class="sr-only">(current)</span></a></li>';
}
elseif ($current_page == $total_pages) { //if it's the last active link
$pagination.= '<li class="page-item active last"><a class="page-link" href="#">' . $current_page . '<span class="sr-only">(current)</span></a></li>';
}
else { //regular current link
$pagination.= '<li class="page-item active"><a class="page-link" href="#">' . $current_page . '<span class="sr-only">(current)</span></a></li>';
}
for ($i = $current_page + 1; $i < $right_links; $i++) { //create right-hand side links
if ($i <= $total_pages) {
$pagination.= '<li class="page-item"><a class="page-link" href="#" data-page="' . $i . '" title="Page ' . $i . '">' . $i . '</a></li>';
}
}
if ($current_page < $total_pages) {
$next_link = ($i > $total_pages) ? $total_pages : $i;
$pagination.= '<li class="page-item"><a class="page-link" href="#" data-page="' . $next_link . '" title="Next">></a></li>'; //next link
$pagination.= '<li class="page-item last"><a class="page-link" href="#" data-page="' . $total_pages . '" title="Last">»</a></li>'; //last link
}
$pagination.= '</ul>';
}
//return pagination links
return $pagination;
}
// Free memory
$rs->free();
// Close connection
$conn->close();
?>
This is the current parsed html of the pager:
<ul class="pagination">
<li class="page-item active first"><a class="page-link" href="#">1<span class="sr-only">(current)</span></a></li>
<li class="page-item"><a class="page-link" href="#" data-page="2" title="Page 2">2</a></li>
<li class="page-item"><a class="page-link" href="#" data-page="3" title="Page 3">3</a></li>
<li class="page-item"><a class="page-link" href="#" data-page="4" title="Next">></a></li>
<li class="page-item last"><a class="page-link" href="#" data-page="4" title="Last">»</a></li>
</ul>

Answer 1

just try like below in your paginate_function()
$next_link = ($i > $total_pages) ? $total_pages : $i;
to
$next_link = (($current_page + 1) > $total_pages) ? $total_pages : $current_page + 1;

Answer 2

Please make changes in paginate_function function as below
if ($current_page < $total_pages) {
$next_link = ($i > $total_pages) ? $total_pages : $i;
$pagination.= '<li class="page-item"><a class="page-link" href="#" data-page="' . $next_link . '" title="Next">></a></li>'; //next link
$pagination.= '<li class="page-item last"><a class="page-link" href="#" data-page="' . $total_pages . '" title="Last">»</a></li>'; //last link
}
Change this to
if ($current_page < $total_pages) {
$next_link = ($i > $total_pages) ? $total_pages : $next;
$pagination.= '<li class="page-item"><a class="page-link" href="#" data-page="' . $next_link . '" title="Next">></a></li>'; //next link
$pagination.= '<li class="page-item last"><a class="page-link" href="#" data-page="' . $total_pages . '" title="Last">»</a></li>'; //last link
}