More simplified way of creating page links dynamically?

Question

A little birdie suggested I bring this question here, so here it goes.

Well I have a working script (see below) but it seems quite clunky and redundant; in my defense I wrote this code many moons ago, but that's not the point. I was curious if anyone has an idea on a more efficient way of writing this code, with less loops and conditionals and, well, noise in the code.

Code in question:

private function pageLinks($num, $page = 1, $search = false, $ne = false) {
 $query = ($search) ? '&query='.$search : null;
 $by = (is_numeric($ne)) ? '&by='.$ne : null;
 $links = 'Page(s):<a href="search.php?page=1' . $query . $by . '" class="tableLink">1</a>';
 $count = 1;
 $npp = $this->numPerPage;
 $buttons = 9;
 $half = 4;
 for($i = 1; $i <= $num; $i++) {
 if(($i%$npp) === 0) {
 $count++;
 }
 }
 if($count < $buttons) {
 for($i = 2; $i <= $count; $i++) {
 $links .= '<a href="search.php?page=' . $i . $query . $by . '" class="tableLink">' . $i . '</a>';
 }
 } elseif($page <= ($half + 2)) {
 for($i = 2; $i <= $buttons; $i++) {
 $links .= '<a href="search.php?page=' . $i . $query . $by . '" class="tableLink">' . $i . '</a>';
 }
 $links .= '...<a href="search.php?page=' . $count . $query . $by . '" class="tableLink">' . $count . '</a>';
 } elseif($page <= ($count - ($half + 2))) {
 $links .= '...';
 for($i = $half; $i > 0; $i--) {
 $links .= '<a href="search.php?page=' . ($page - $i) . $query . $by . '" class="tableLink">' . ($page - $i) . '</a>';
 }
 $links .= '<a href="search.php?page=' . ($page - $i) . $query . $by . '" class="tableLink">' . ($page - $i) . '</a>';
 for($i = 1; $i <= $half; $i++) {
 $links .= '<a href="search.php?page=' . ($page + $i) . $query . $by . '" class="tableLink">' . ($page + $i) . '</a>';
 }
 $links .= '...<a href="search.php?page=' . $count . $query . $by . '" class="tableLink">' . $count . '</a>';
 } else {
 $links .= '...';
 for($i = $buttons - 1; $i >= 0; $i--) {
 $links .= '<a href="search.php?page=' . ($count - $i) . $query . $by . '" class="tableLink">' . ($count - $i) . '</a>';
 }
 }
 return($links);
}

The method is called like so:

$links = $this->pageLinks($count, $page, $url, $ne);

And the variables are as such:

$count = total number of clients in database (int)
$page = current page to build from (int)
$url = the name or email for the search (String)
$ne = is for the search string either by name (1) or email (2) (int)

And the output is something like (as links):

Page(s):1 2 3 4 5 6 7 8 9...33

Or if you're in the middle (page 20):

Page(s):1...16 17 18 19 20 21 22 23 24...33

Now this isn't always called through a search function, hence the default values for $url and $ne, but that's not very important. My question is there a cleaner way to handle building of these links? Or am I stuck with this cluster of loops?

Answer 1

This:

$count = 1;
for($i = 1; $i <= $num; $i++) {
 if(($i%$npp) === 0) {
 $count++;
 }
}

is equivalent to

$count = floor($num / $npp) + 1;

As for the paging, I'd do it like this:

$from = $page - $half;
if ($from <= 2) $from = 2;
$to = $page + $half;
if ($to >= $count - 1) $to = $count - 1;
$extra = $query . $by;
$links = $this->pageLink(1, $extra);
if ($from > 2) $links .= "...";
for ($i = $from; $i <= $to; $i++)
 $links .= $this->pageLink($i, $extra);
if ($i < $count) $links .= "..."; // I use $i instead of $to because $i == $to + 1, so I save one addition
$links = $this->pageLink($count, $extra);

Here, you also need:

private function pageLink($num, $extra) {
 return '<a href="search.php?page=' . $num . $extra . '" class="tableLink">' . $num . '</a>';
}

This was written by heart, so be weary of the possible bugs.

• faino: Genius! Works like a charm! Only bug was a missing $ in the pageLink method, but that's the least of my worries. Wow, it's.. beautiful. Thank you, very informative and exactly what I was looking for.
• Vedran Šego: I've fixed it. Thank you for that, and I'm glad I've been able to help.