我在PHP中观看了关于分页的视频教程。作者在他的教程中使用了第四版PHP。现在，我想分页我的评论页面。我使用了我在教程中学到的代码。像这样的代码：
$limit = 10;
$page = $_GET['page'];
if(($page='') or !is_numeric($page)){
$page = 1;
}
$total_posts = mysql_num_rows(mysql_query("SELECT * FROM comments"));
$total_pages = ceil($total_posts / $limit);
$start = ($page-1)*$limit;
$query = mysql_query("SELECT * FROM comments ORDER BY likes DESC LIMIT $start,$limit");
while($write = mysql_fetch_array($query)){
$id = $write['id'];
$comment = $write['comment'];
$likes = $write['likes'];
echo $id . ' ' . $comment . ' ' . $likes . '<br>' ;
}
但是，当我对页面进行分页时，页面内容不会改变。例如，“comments.php？page = 1”中的注释与“comments.php？page = 2”相同。
它取决于PHP的版本吗？ （因为，这段代码在视频教程中有效） 请帮我找出问题所在。
答案 0 :(得分：7)
or的工作方式与||
尝试使用||代替
同时
无论如何，您都会在每个页面加载时设置$page = ''。所以总是第1页
if(($page='') or !is_numeric($page)){ //!!!ahhh
$page = 1;
}
将其更改为：
if(($page == '') || !is_numeric($page)){
$page = 1;
}
答案 1 :(得分：3)
试试这个：
<?php
/*
Place code to connect to your DB here.
*/
include('config.php'); // include your code to connect to DB.
$tbl_name=""; //your table name
// How many adjacent pages should be shown on each side?
$adjacents = 3;
/*
First get total number of rows in data table.
If you have a WHERE clause in your query, make sure you mirror it here.
*/
$query = "SELECT COUNT(*) as num FROM $tbl_name";
$total_pages = mysql_fetch_array(mysql_query($query));
$total_pages = $total_pages[num];
/* Setup vars for query. */
$targetpage = "filename.php"; //your file name (the name of this file)
$limit = 2; //how many items to show per page
$page = $_GET['page'];
if($page)
$start = ($page - 1) * $limit; //first item to display on this page
else
$start = 0; //if no page var is given, set start to 0
/* Get data. */
$sql = "SELECT column_name FROM $tbl_name LIMIT $start, $limit";
$result = mysql_query($sql);
/* Setup page vars for display. */
if ($page == 0) $page = 1; //if no page var is given, default to 1.
$prev = $page - 1; //previous page is page - 1
$next = $page + 1; //next page is page + 1
$lastpage = ceil($total_pages/$limit); //lastpage is = total pages / items per page, rounded up.
$lpm1 = $lastpage - 1; //last page minus 1
/*
Now we apply our rules and draw the pagination object.
We're actually saving the code to a variable in case we want to draw it more than once.
*/
$pagination = "";
if($lastpage > 1)
{
$pagination .= "<div class=\"pagination\">";
//previous button
if ($page > 1)
$pagination.= "<a href=\"$targetpage?page=$prev\">� previous</a>";
else
$pagination.= "<span class=\"disabled\">� previous</span>";
//pages
if ($lastpage < 7 + ($adjacents * 2)) //not enough pages to bother breaking it up
{
for ($counter = 1; $counter <= $lastpage; $counter++)
{
if ($counter == $page)
$pagination.= "<span class=\"current\">$counter</span>";
else
$pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";
}
}
elseif($lastpage > 5 + ($adjacents * 2)) //enough pages to hide some
{
//close to beginning; only hide later pages
if($page < 1 + ($adjacents * 2))
{
for ($counter = 1; $counter < 4 + ($adjacents * 2); $counter++)
{
if ($counter == $page)
$pagination.= "<span class=\"current\">$counter</span>";
else
$pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";
}
$pagination.= "...";
$pagination.= "<a href=\"$targetpage?page=$lpm1\">$lpm1</a>";
$pagination.= "<a href=\"$targetpage?page=$lastpage\">$lastpage</a>";
}
//in middle; hide some front and some back
elseif($lastpage - ($adjacents * 2) > $page && $page > ($adjacents * 2))
{
$pagination.= "<a href=\"$targetpage?page=1\">1</a>";
$pagination.= "<a href=\"$targetpage?page=2\">2</a>";
$pagination.= "...";
for ($counter = $page - $adjacents; $counter <= $page + $adjacents; $counter++)
{
if ($counter == $page)
$pagination.= "<span class=\"current\">$counter</span>";
else
$pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";
}
$pagination.= "...";
$pagination.= "<a href=\"$targetpage?page=$lpm1\">$lpm1</a>";
$pagination.= "<a href=\"$targetpage?page=$lastpage\">$lastpage</a>";
}
//close to end; only hide early pages
else
{
$pagination.= "<a href=\"$targetpage?page=1\">1</a>";
$pagination.= "<a href=\"$targetpage?page=2\">2</a>";
$pagination.= "...";
for ($counter = $lastpage - (2 + ($adjacents * 2)); $counter <= $lastpage; $counter++)
{
if ($counter == $page)
$pagination.= "<span class=\"current\">$counter</span>";
else
$pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";
}
}
}
//next button
if ($page < $counter - 1)
$pagination.= "<a href=\"$targetpage?page=$next\">next �</a>";
else
$pagination.= "<span class=\"disabled\">next �</span>";
$pagination.= "</div>\n";
}
?>
<?php
while($row = mysql_fetch_array($result))
{
// Your while loop here
}
?>
答案 2 :(得分：1)
即使代码可能已过时，但为什么它不起作用的是$page - if在顶部（请参阅Neals answer）。
接下来，您查询所有评论以获取评论数量，这是一团糟。分页的好处是不查询所有注释，而只查询一部分。让我们简化你的例子：
// configuration
$limit = 10; # comments per page
// input
$page = isset($_GET['page']) ? $_GET['page'] : 1; # page to display
$page = max(1, $page); # minimum value is 1
// get number of comments
list($total_posts) = mysql_fetch_array(mysql_query("SELECT COUNT(*) FROM comments"));
$total_pages = min(1, ceil($total_posts/$limit)); # even with no commment, total pages is 1
$page = min($page, $total_pages); # the maximum page number is total pages
// get this page's comments
$start = ($page-1)*$limit; # row offset
$query = mysql_query("SELECT * FROM comments ORDER BY likes DESC LIMIT $start, $limit");
// output
while ($write = mysql_fetch_array($query))
{
$id = $write['id'];
$comment = $write['comment'];
$likes = $write['likes'];
echo $id . ' ' . $comment . ' ' . $likes . '<br>' ;
}
答案 3 :(得分：1)
通常使用
是一种很好的做法if ( "" == $page )
而不是
if( $page == "" )
由于显而易见的原因，我是一个像这样的拼写错误的情况，你最终会看到一个错误，而不是一个不希望的变量赋值给一个很难捕获/调试的字符串。
答案 4 :(得分：0)
请使用此代码这是简单的PHP和MySQL，CSS不是Jquery或任何js
<?php
// You have to put your mysql connection data and alter the SQL queries(both queries)
mysql_connect("DB_Host_Here","DB_Username_Here","DB_Password_Here") or die (mysql_error());
mysql_select_db("DB_Name_Here") or die (mysql_error());
////////////// QUERY THE MEMBER DATA INITIALLY LIKE YOU NORMALLY WOULD
$sql = mysql_query("SELECT id, firstname, country FROM myTable ORDER BY id ASC");
//////////////////////////////////// Adam's Pagination Logic ////////////////////////////////////////////////////////////////////////
$nr = mysql_num_rows($sql); // Get total of Num rows from the database query
if (isset($_GET['pn'])) { // Get pn from URL vars if it is present
$pn = preg_replace('#[^0-9]#i', '', $_GET['pn']); // filter everything but numbers for security(new)
//$pn = ereg_replace("[^0-9]", "", $_GET['pn']); // filter everything but numbers for security(deprecated)
} else { // If the pn URL variable is not present force it to be value of page number 1
$pn = 1;
}
//This is where we set how many database items to show on each page
$itemsPerPage = 10;
// Get the value of the last page in the pagination result set
$lastPage = ceil($nr / $itemsPerPage);
// Be sure URL variable $pn(page number) is no lower than page 1 and no higher than $lastpage
if ($pn < 1) { // If it is less than 1
$pn = 1; // force if to be 1
} else if ($pn > $lastPage) { // if it is greater than $lastpage
$pn = $lastPage; // force it to be $lastpage's value
}
// This creates the numbers to click in between the next and back buttons
// This section is explained well in the video that accompanies this script
$centerPages = "";
$sub1 = $pn - 1;
$sub2 = $pn - 2;
$add1 = $pn + 1;
$add2 = $pn + 2;
if ($pn == 1) {
$centerPages .= ' <span class="pagNumActive">' . $pn . '</span> ';
$centerPages .= ' <a href="' . $_SERVER['PHP_SELF'] . '?pn=' . $add1 . '">' . $add1 . '</a> ';
} else if ($pn == $lastPage) {
$centerPages .= ' <a href="' . $_SERVER['PHP_SELF'] . '?pn=' . $sub1 . '">' . $sub1 . '</a> ';
$centerPages .= ' <span class="pagNumActive">' . $pn . '</span> ';
} else if ($pn > 2 && $pn < ($lastPage - 1)) {
$centerPages .= ' <a href="' . $_SERVER['PHP_SELF'] . '?pn=' . $sub2 . '">' . $sub2 . '</a> ';
$centerPages .= ' <a href="' . $_SERVER['PHP_SELF'] . '?pn=' . $sub1 . '">' . $sub1 . '</a> ';
$centerPages .= ' <span class="pagNumActive">' . $pn . '</span> ';
$centerPages .= ' <a href="' . $_SERVER['PHP_SELF'] . '?pn=' . $add1 . '">' . $add1 . '</a> ';
$centerPages .= ' <a href="' . $_SERVER['PHP_SELF'] . '?pn=' . $add2 . '">' . $add2 . '</a> ';
} else if ($pn > 1 && $pn < $lastPage) {
$centerPages .= ' <a href="' . $_SERVER['PHP_SELF'] . '?pn=' . $sub1 . '">' . $sub1 . '</a> ';
$centerPages .= ' <span class="pagNumActive">' . $pn . '</span> ';
$centerPages .= ' <a href="' . $_SERVER['PHP_SELF'] . '?pn=' . $add1 . '">' . $add1 . '</a> ';
}
// This line sets the "LIMIT" range... the 2 values we place to choose a range of rows from database in our query
$limit = 'LIMIT ' .($pn - 1) * $itemsPerPage .',' .$itemsPerPage;
// Now we are going to run the same query as above but this time add $limit onto the end of the SQL syntax
// $sql2 is what we will use to fuel our while loop statement below
$sql2 = mysql_query("SELECT id, firstname, country FROM myTable ORDER BY id ASC $limit");
//////////////////////////////// END Adam's Pagination Logic ////////////////////////////////////////////////////////////////////////////////
///////////////////////////////////// Adam's Pagination Display Setup /////////////////////////////////////////////////////////////////////
$paginationDisplay = ""; // Initialize the pagination output variable
// This code runs only if the last page variable is ot equal to 1, if it is only 1 page we require no paginated links to display
if ($lastPage != "1"){
// This shows the user what page they are on, and the total number of pages
$paginationDisplay .= 'Page <strong>' . $pn . '</strong> of ' . $lastPage. ' ';
// If we are not on page 1 we can place the Back button
if ($pn != 1) {
$previous = $pn - 1;
$paginationDisplay .= ' <a href="' . $_SERVER['PHP_SELF'] . '?pn=' . $previous . '"> Back</a> ';
}
// Lay in the clickable numbers display here between the Back and Next links
$paginationDisplay .= '<span class="paginationNumbers">' . $centerPages . '</span>';
// If we are not on the very last page we can place the Next button
if ($pn != $lastPage) {
$nextPage = $pn + 1;
$paginationDisplay .= ' <a href="' . $_SERVER['PHP_SELF'] . '?pn=' . $nextPage . '"> Next</a> ';
}
}
///////////////////////////////////// END Adam's Pagination Display Setup ///////////////////////////////////////////////////////////////////////////
// Build the Output Section Here
$outputList = '';
while($row = mysql_fetch_array($sql2)){
$id = $row["id"];
$firstname = $row["firstname"];
$country = $row["country"];
$outputList .= '<h1>' . $firstname . '</h1><h2>' . $country . ' </h2><hr />';
} // close while loop
?>
<html>
<head>
<title>Adam's Pagination</title>
<style type="text/css">
<!--
.pagNumActive {
color: #000;
border:#060 1px solid; background-color: #D2FFD2; padding-left:3px; padding-right:3px;
}
.paginationNumbers a:link {
color: #000;
text-decoration: none;
border:#999 1px solid; background-color:#F0F0F0; padding-left:3px; padding-right:3px;
}
.paginationNumbers a:visited {
color: #000;
text-decoration: none;
border:#999 1px solid; background-color:#F0F0F0; padding-left:3px; padding-right:3px;
}
.paginationNumbers a:hover {
color: #000;
text-decoration: none;
border:#060 1px solid; background-color: #D2FFD2; padding-left:3px; padding-right:3px;
}
.paginationNumbers a:active {
color: #000;
text-decoration: none;
border:#999 1px solid; background-color:#F0F0F0; padding-left:3px; padding-right:3px;
}
-->
</style>
</head>
<body>
<div style="margin-left:64px; margin-right:64px;">
<h2>Total Items: <?php echo $nr; ?></h2>
</div>
<div style="margin-left:58px; margin-right:58px; padding:6px; background-color:#FFF; border:#999 1px solid;"><?php echo $paginationDisplay; ?></div>
<div style="margin-left:64px; margin-right:64px;"><?php print "$outputList"; ?></div>
<div style="margin-left:58px; margin-right:58px; padding:6px; background-color:#FFF; border:#999 1px solid;"><?php echo $paginationDisplay; ?></div>
</body>
</html>
答案 5 :(得分：0)
Try this. Its perfect and working very fine.
<?php
$cur_rre_nt_page=isset($_GET['p'])?$_GET['p']:1;
$records_per_page=(isset($manual_limit)&&$manual_limit>0)?$manual_limit:5;// set limit in $manual_limit before including this file if you want to add manual limit
$page_limit=5; // Links to be shown on a page this must be odd number like and greater than 1 like 1,3,5,7,9..
$total_pages=ceil($num_totrec/$records_per_page);
$var_limit=" LIMIT ".(($cur_rre_nt_page-1)*$records_per_page).",$records_per_page";
$var_file_url=$current_file_front_end;
if($total_pages<=1)
{
$page_links='';
}
else
{
if($cur_rre_nt_page<=ceil($page_limit/2))
{
$page_link="<a tabindex=\"0\" href=\"$var_file_url?p=1\" class=\"first paginate_button\" id=\"DataTables_Table_0_first\">First</a>";
$page_link.=$cur_rre_nt_page>1?"<a tabindex=\"0\" href=\"$var_file_url?p=".($cur_rre_nt_page-1)."$str_url\" class=\"first paginate_button\" id=\"DataTables_Table_0_first\">Previous</a>":'';
for($i=1;$i<=$page_limit;$i++)
{
if($i<=$total_pages)
{
if($i==$cur_rre_nt_page)
{
$page_link.="<span class=\"paginate_active\">$i</span>";
}
else
{
$page_link.="<a href=\"$var_file_url?p=$i$str_url\" class=\"paginate_button\" id=\"DataTables_Table_$i\">$i</a>";
}
if($i==$page_limit && $i<$total_pages)
{
$page_link.='...';
}
}
}
$page_link.=($cur_rre_nt_page<$total_pages)?"<a tabindex=\"0\" href=\"$var_file_url?p=".($cur_rre_nt_page+1)."$str_url\" class=\"first paginate_button\" id=\"DataTables_Table_0_nextt\">Next</a>":'';
$page_link.="<a tabindex=\"0\" href=\"$var_file_url?p=$total_pages$str_url\" class=\"last paginate_button\" id=\"DataTables_Table_0_last\">Last</a>";
}
elseif($cur_rre_nt_page<=($total_pages-ceil($page_limit/2)))
{
$page_link="<a tabindex=\"0\" href=\"$var_file_url?p=1\" class=\"first paginate_button\" id=\"DataTables_Table_0_first\">First</a>";
$page_link.="<a tabindex=\"0\" href=\"$var_file_url?p=".($cur_rre_nt_page-1)."$str_url\" class=\"first paginate_button\" id=\"DataTables_Table_0_first\">Previous</a>...";
for($i=$cur_rre_nt_page-floor($page_limit/2);$i<=$cur_rre_nt_page+floor($page_limit/2);$i++)
{
if($i==$cur_rre_nt_page)
{
$page_link.="<span class=\"paginate_active\">$i</span>";
}
else
{
$page_link.="<a href=\"$var_file_url?p=$i$str_url\" class=\"paginate_button\" id=\"DataTables_Table_$i\">$i</a>";
}
if($i==$cur_rre_nt_page+floor($page_limit/2) && $i<$total_pages)
{
$page_link.="...";
}
}
$page_link.="<a tabindex=\"0\" href=\"$var_file_url?p=".($cur_rre_nt_page+1)."$str_url\" class=\"first paginate_button\" id=\"DataTables_Table_0_nextt\">Next</a>";
$page_link.="<a tabindex=\"0\" href=\"$var_file_url?p=$total_pages$str_url\" class=\"last paginate_button\" id=\"DataTables_Table_0_last\">Last</a>";
}
else
{
$page_link="<a tabindex=\"0\" href=\"$var_file_url?p=1\" class=\"first paginate_button\" id=\"DataTables_Table_0_first\">First</a>";
$page_link.="<a tabindex=\"0\" href=\"$var_file_url?p=".($cur_rre_nt_page-1)."$str_url\" class=\"first paginate_button\" id=\"DataTables_Table_0_previous\">Previous</a>";
$page_link.=$total_pages>$page_limit?'...':'';
for($i=$total_pages-$page_limit+1;$i<=$total_pages;$i++)
{
if($i==$cur_rre_nt_page)
{
$page_link.="<span class=\"paginate_active\">$i</span>";
}
else
{
$page_link.="<a href=\"$var_file_url?p=$i$str_url\" class=\"paginate_button\" id=\"DataTables_Table_$i\">$i</a>";
}
}
$page_link.=($cur_rre_nt_page<$total_pages)?"<a tabindex=\"0\" href=\"$var_file_url?p=".($cur_rre_nt_page+1)."$str_url\" class=\"first paginate_button\" id=\"DataTables_Table_0_nextt\">Next</a>":"";
$page_link.="<a tabindex=\"0\" href=\"$var_file_url?p=$total_pages$str_url\" class=\"last paginate_button\" id=\"DataTables_Table_0_last\">Last</a>";
}
}
?>