限制最大页码并添加上一页和下一页按钮
Limiting maximum page numbering and adding Previous and Next button
我正在使用文本文件作为数据库而不是使用 mySQL 创建分页。大部分已经完成,唯一的问题是页码本身。如何限制底部的最大页码?在我按下最后一个页码后是否可以转到下一组页面?
是这样的PREV 1 2 3 4 5 NEXT
<?php
// connect to txt database
$file="database.txt";
$con = file_get_contents($file);
// define how many results you want per page
$results_per_page = 5;
// find out the number of results stored in database
$linecount = 0;
$handle = fopen($file, "r");
while(!feof($handle)){
$line = fgets($handle);
$linecount++;
}
fclose($handle);
$number_of_results = $linecount;
// determine number of total pages available
$number_of_pages = ceil($number_of_results/$results_per_page);
// determine which page number visitor is currently on
if (!isset($_GET['page'])) {
$page = 1;
} else {
$page = $_GET['page'];
}
// display the links to the pages
for ($page=1;$page<=5;$page++) {
echo '<a href="index.php?page=' . $page . '">' . $page . '</a> ';
}
?>
我看到您正在使用数据库。如果您使用 CMS,这会更容易,但无论如何请检查您是否能理解此脚本:
try {
// Find out how many items are in the table
$total = $dbh->query('
SELECT
COUNT(*)
FROM
table
')->fetchColumn();
// How many items to list per page
$limit = 20;
// How many pages will there be
$pages = ceil($total / $limit);
// What page are we currently on?
$page = min($pages, filter_input(INPUT_GET, 'page', FILTER_VALIDATE_INT, array(
'options' => array(
'default' => 1,
'min_range' => 1,
),
)));
// Calculate the offset for the query
$offset = ($page - 1) * $limit;
// Some information to display to the user
$start = $offset + 1;
$end = min(($offset + $limit), $total);
// The "back" link
$prevlink = ($page > 1) ? '<a href="?page=1" title="First page">«</a> <a href="?page=' . ($page - 1) . '" title="Previous page">‹</a>' : '<span class="disabled">«</span> <span class="disabled">‹</span>';
// The "forward" link
$nextlink = ($page < $pages) ? '<a href="?page=' . ($page + 1) . '" title="Next page">›</a> <a href="?page=' . $pages . '" title="Last page">»</a>' : '<span class="disabled">›</span> <span class="disabled">»</span>';
// Display the paging information
echo '<div id="paging"><p>', $prevlink, ' Page ', $page, ' of ', $pages, ' pages, displaying ', $start, '-', $end, ' of ', $total, ' results ', $nextlink, ' </p></div>';
// Prepare the paged query
$stmt = $dbh->prepare('
SELECT
*
FROM
table
ORDER BY
name
LIMIT
:limit
OFFSET
:offset
');
// Bind the query params
$stmt->bindParam(':limit', $limit, PDO::PARAM_INT);
$stmt->bindParam(':offset', $offset, PDO::PARAM_INT);
$stmt->execute();
// Do we have any results?
if ($stmt->rowCount() > 0) {
// Define how we want to fetch the results
$stmt->setFetchMode(PDO::FETCH_ASSOC);
$iterator = new IteratorIterator($stmt);
// Display the results
foreach ($iterator as $row) {
echo '<p>', $row['name'], '</p>';
}
} else {
echo '<p>No results could be displayed.</p>';
}
} catch (Exception $e) {
echo '<p>', $e->getMessage(), '</p>';
}
到处都有注释,应该很容易理解。
图片来源:Nev Stokes
我正在使用文本文件作为数据库而不是使用 mySQL 创建分页。大部分已经完成,唯一的问题是页码本身。如何限制底部的最大页码?在我按下最后一个页码后是否可以转到下一组页面?
是这样的PREV 1 2 3 4 5 NEXT
<?php
// connect to txt database
$file="database.txt";
$con = file_get_contents($file);
// define how many results you want per page
$results_per_page = 5;
// find out the number of results stored in database
$linecount = 0;
$handle = fopen($file, "r");
while(!feof($handle)){
$line = fgets($handle);
$linecount++;
}
fclose($handle);
$number_of_results = $linecount;
// determine number of total pages available
$number_of_pages = ceil($number_of_results/$results_per_page);
// determine which page number visitor is currently on
if (!isset($_GET['page'])) {
$page = 1;
} else {
$page = $_GET['page'];
}
// display the links to the pages
for ($page=1;$page<=5;$page++) {
echo '<a href="index.php?page=' . $page . '">' . $page . '</a> ';
}
?>
我看到您正在使用数据库。如果您使用 CMS,这会更容易,但无论如何请检查您是否能理解此脚本:
try {
// Find out how many items are in the table
$total = $dbh->query('
SELECT
COUNT(*)
FROM
table
')->fetchColumn();
// How many items to list per page
$limit = 20;
// How many pages will there be
$pages = ceil($total / $limit);
// What page are we currently on?
$page = min($pages, filter_input(INPUT_GET, 'page', FILTER_VALIDATE_INT, array(
'options' => array(
'default' => 1,
'min_range' => 1,
),
)));
// Calculate the offset for the query
$offset = ($page - 1) * $limit;
// Some information to display to the user
$start = $offset + 1;
$end = min(($offset + $limit), $total);
// The "back" link
$prevlink = ($page > 1) ? '<a href="?page=1" title="First page">«</a> <a href="?page=' . ($page - 1) . '" title="Previous page">‹</a>' : '<span class="disabled">«</span> <span class="disabled">‹</span>';
// The "forward" link
$nextlink = ($page < $pages) ? '<a href="?page=' . ($page + 1) . '" title="Next page">›</a> <a href="?page=' . $pages . '" title="Last page">»</a>' : '<span class="disabled">›</span> <span class="disabled">»</span>';
// Display the paging information
echo '<div id="paging"><p>', $prevlink, ' Page ', $page, ' of ', $pages, ' pages, displaying ', $start, '-', $end, ' of ', $total, ' results ', $nextlink, ' </p></div>';
// Prepare the paged query
$stmt = $dbh->prepare('
SELECT
*
FROM
table
ORDER BY
name
LIMIT
:limit
OFFSET
:offset
');
// Bind the query params
$stmt->bindParam(':limit', $limit, PDO::PARAM_INT);
$stmt->bindParam(':offset', $offset, PDO::PARAM_INT);
$stmt->execute();
// Do we have any results?
if ($stmt->rowCount() > 0) {
// Define how we want to fetch the results
$stmt->setFetchMode(PDO::FETCH_ASSOC);
$iterator = new IteratorIterator($stmt);
// Display the results
foreach ($iterator as $row) {
echo '<p>', $row['name'], '</p>';
}
} else {
echo '<p>No results could be displayed.</p>';
}
} catch (Exception $e) {
echo '<p>', $e->getMessage(), '</p>';
}
到处都有注释,应该很容易理解。
图片来源:Nev Stokes