问PHP中的分页(分页注释)

EN

if(($page='') or !is_numeric($page)){ //!!!ahhh
    $page   = 1;
}

if(($page == '') || !is_numeric($page)){
   $page = 1;
}

<?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

    }
?>

// 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>' ;    
}