Advanced Pagination (Tutorials » PHP)

<?php
/**
 * The pagination function. Creates a list of links if multiple pages
 * @param int $pages : The number of pages
 * @param int $page : The current page number
 * @param int $show  : The number of links in each direction (of the current page) to show
 * @param string $pre : What to prefix each link with (what comes before the page number)
 * @param string $post : What to suffix each link with (what comes after the page number)
 * @return string : The pagination
 */
function pagination($pages, $page, $show=2, $pre='?page=', $post='')
{
	// $p is the output of the pagination function. Note the .= on future expressions regarding $p
	$p = 'Viewing page <b>'. $page .'</b> of <b>'. $pages .'</b>';
	
	// only show pagination if there is more than one page
	if( $pages > 1 )
	{
		// $first whether or not to show a link to the first page, and a "back" link
		$first = $page>1;
		
		// $last whether or not to show a link to the last page, and a "next" link
		$last = $page<$pages;
		
		// only link to previous page if there _is_ a previous page but show the text regardless
		$p .= '<br />'. ($first? '<a href="'. $pre . ($page-1) . $post .'" title="Go back a page (page '. ($page-1) .')">' : '') .'<b>&lsaquo;</b>- Back'. ($first? '</a>' : '') .' &nbsp; &nbsp; ';
		
		// only _link_ to the first page if we arent already on the first page but show the text regardless
		$p .= ($first? '<a href="'. $pre . 1 . $post .'" title="Go to the first page">' : '') .'&laquo;'. ($first? '</a>' : '');
		
		// the starting number of pages to show
		$min = $pages-$show-1;
		
		// the last page number to show
		$max = $pages+$show+1;
		
		// means that there are pages before the starting page we are showing so lets add ... to show this
		if( $min > 1 )
		{
			$p .= ' ...';
		}
		
		// make sure $min is at least 1
		if( $min < 1 )
		{
			$min = 1;
		}
		
		// make sure we dont show more pages than there are
		if( $max > $pages )
		{
			$max = $pages;
		}
		
		// start $i at $min (the first page number to show) and end it when $i is > $max (after $i is greater than the last page to show)
		for( $i=$min; $i<=$max; $i++ )
		{
			// set $b for reference to it the second time
			// if $i==$page means it is the current page so dont link it, instead make it bold with [] around it
			$p .= (($b=($i==$page))? ' <b>[' : ' <a href="'. $pre . $i . $post .'" title="Go to page '. $i .'">'). $i .($b? ']</b>' : '</a>');
		}
		
		// means there are pages after the last page we are showing so lets add ... to show this
		if( $max < $pages )
		{
			$p .= ' ...';
		}
		
		// only _link_ it if we are not already on the last page but display the raquo regardless
		$p .= ($last? ' <a href="'. $pre . $pages . $post .'" title="Go to the last page (page '. $pages .')">' : ' ') .'&raquo;'. ($last? '</a>' : '');
		
		// only _link_ to the next page if there _is_ a next page but show the text regardless
		$p .= ($last? ' &nbsp; &nbsp; <a href="'. $pre . ($page+1) . $post .'" title="Go to next (page '. ($page+1) .')">' : '') .'Next -<b>&rsaquo;</b>'. ($last? '</a>' : '');

	}
	
	// return $p containing all the pagination. Wrap $p with whatever html container you need for styling etc for now lets just center the text
	return '<div style="text-align: center;">'. $p .'</div>';
}
?>

<?php
// This would return up to 10 rows and only where page=5
$q = mysql_query("SELECT SQL_CALC_FOUND_ROWS id, name, comment FROM comments WHERE page=5 LIMIT 0, 10");

// to get the number of rows that SQL_CALC_FOUND_ROWS calculated, a second query is needed (needs to be the NEXT query after SQL_CALC_FOUND_ROWS)
$rowcount = mysql_result(mysql_query("SELECT FOUND_ROWS()"), 0);
?>

<?php
// get the roowcount
$rowcount = mysql_result(mysql_query("SELECT COUNT(*) FROM comments WHERE page=5"), 0);

// perform the query that actually fetches the data we want
$q = mysql_query("SELECT id, name, comment FROM comments WHERE page=5 LIMIT 0, 10");
?>

<?php
// how many results per page
$perpage = 10;

// the current page to show
$page = (int)$_GET['page'];

// make sure $page is valid. If no page was specified default to 1
if( $page < 1 )
{
	$page = 1;
}

// $perpage * $page is a minimum of 10, rows start at 0, so subtract $perpage from from this number.
$rowstart = ($perpage*$page)-$perpage;

// perform our query
$q = mysql_query("SELECT SQL_CALC_ROWS id, name, comment
	FROM comments
	WHERE page=5
	LIMIT $rowstart, $perpage");

// get the rowcount. This is the total number of rows matching our WHERE
$rowcount = mysql_result(mysql_query("SELECT FOUND_ROWS()"), 0);

// only continue if there are any rows from the current page
if( mysql_num_rows($q) )
{
	// the number of pages will be ceil() of $rowcount/$perpage.
	// ceil ALWAYS rounds UP. This is what we want, if there is only ONE result on the last page we still want it to be a page. you can read more at php.net/ceil
	$pages = ceil($rowcount/$perpage);
	
	// set $pagination to the return value of pagination so we can use it again as well as echo it.
	echo ($pagination = pagination($pages, $page));
	
	// fetch each row from the result set
	while( ($f = mysql_fetch_array($q, MYSQL_ASSOC)) )
	{
		// do what you need to do with each row
	}
	
	// display pagination at the end of the page too If you dont need to use it twice, just echo pagination() without storing it to $pagination above
	echo $pagination;
}
?>