可移植性强一点的分页程序

function multi($num, $perpage, $curr_page, $mpurl) {
$multipage = '';
if($num > $perpage) {
$page = 10;
$offset = 2;

$pages = ceil($num / $perpage);
$from = $curr_page - $offset;
$to = $curr_page + $page - $offset - 1;
if($page > $pages) {
$from = 1;
$to = $pages;
} else {
if($from < 1) {
$to = $curr_page + 1 - $from;
$from = 1;
if(($to - $from) < $page && ($to - $from) < $pages) {
$to = $page;
}
} elseif($to > $pages) {
$from = $curr_page - $pages + $to;
$to = $pages;
if(($to - $from) < $page && ($to - $from) < $pages) {
$from = $pages - $page + 1;
}
}
}
$multipage .= "<a href=\"$mpurl&page=1\">&lt;&lt;</a> ";
for($i = $from; $i <= $to; $i++) {
if($i != $curr_page) {
$multipage .= "<a href=\"$mpurl&page=$i\">[$i]</a> ";
} else {
$multipage .= '<u><b>['.$i.']</b></u> ';
}
}
$multipage .= $pages > $page ? " ... <a href=\"$mpurl&page=$pages\"> [$pages] &gt;&gt;</a>" : " <a href=\"$mpurl&page=$pages\">&gt;&gt;</a>";
}
return $multipage;
}