像stackoverflow一样分页

Question

我是php的新手,特别是在制作分页时.

我的问题是,如何使分页像stackoverflow的分页？
我的意思是这样的分页:

1 ... 5 6 7 8 9 ... 25
(第一个数字和最后一个数字总是出现,但在中间只有5个数字,所选页面绝对在中间)

在PHP我已经尝试过分页,

<?php

//Show page links
for($i=1; $i<=$pages; $i++)
{
    echo '<li id="'.$i.'">'.$i.'</li>';
}

?>

但它会显示所有页面,如

1 2 3 4 5 6 7 8 9 10等

任何机构都有简单的逻辑例子来解决这个问题？
非常感谢 :)

Answer 1

这将生成上面的数字,其中current = 7,pages = 25.用链接替换数字以获得实际的分页索引.

$current = 7;
$pages = 25;
$links = array();

if ($pages > 3) {
    // this specifies the range of pages we want to show in the middle
    $min = max($current - 2, 2);
    $max = min($current + 2, $pages-1);

    // we always show the first page
    $links[] = "1";

    // we're more than one space away from the beginning, so we need a separator
    if ($min > 2) {
        $links[] = "...";
    }

    // generate the middle numbers
    for ($i=$min; $i<$max+1; $i++) {
        $links[] = "$i";
    }

    // we're more than one space away from the end, so we need a separator
    if ($max < $pages-1) {
        $links[] = "...";
    }
    // we always show the last page
    $links[] = "$pages";
} else {
    // we must special-case three or less, because the above logic won't work
    $links = array("1", "2", "3");
}
echo implode(" ", $links);

输出:

1 ... 5 6 7 8 9 ... 25

Answer 2

下面是我几年前写的一般分页类¹的片段.我编辑它只显示相关部分.

// cntAround is the number of pages to show before and after the current
function renderNavigation($cntAround = 1) {
    $out      = '';
    $isGap    = false; // A "gap" is the pages to skip
    $current  = // Current page
    $cntPages = // Total number of pages

    for ($i = 0; $i < $pages; $i++) { // Run through pages
        $isGap = false;

        // Are we at a gap?
        if ($cntAround >= 0 && $i > 0 && $i < $cntPages - 1 && abs($i - $current) > $cntAround) { // If beyond "cntAround" and not first or last.
            $isGap    = true;

            // Skip to next linked item (or last if we've already run past the current page)
            $i = ($i < $current ? $current - $cntAround : $cntPages - 1) - 1;
        }

        $lnk = ($isGap ? '...' : ($i + 1)); // If gap, write ellipsis, else page number
        if ($i != $current && !$isGap) { // Do not link gaps and current
            $lnk = '<a href="?page=' . ($i + 1) . '">' . $lnk . '</a>';
        }
        $out .= "\t<li>" . $lnk . "</li>\n"; // Wrap in list items
    }

    return "<ul>\n" . $out . '</ul>'; // Wrap in list
}

例1

cntAround = 1,current = 5,cntPages = 9:

[1] ... [4] 5 [6] ... [9]

例2

cntAround = 3,current = 5,cntPages = 11:

[1] [2] [3] [4] 5 [6] [7] [8] ... [11]

¹⁾文章是丹麦语.谷歌翻译版本在这里.