php - 多次出现 \r\n 需要替换为

Question

我需要将多次出现的<br />, <br>, <br/>, \r, \n,\r\n替换为仅 1 ，但仅在它一起显示的地方，以便我可以将段落拆分为一个数组并在字符串末尾修剪掉标记<br />的最后一个换行符...br

字符串的示例如下：

This is paragraph 1<br>

This is paragraph 2<br /><br>



This is paragraph 3
This is paragraph 4


This is paragraph 5<br/>
This is paragraph 6


This is paragraph 7<br />This is paragraph 8

This is paragraph 9<br>

我试过的：

$description = !empty($results['Description']) ? strip_tags(rtrim(str_replace(array("\n", "\r", "\r\n", "<br>", "<br/>", "<br />"), array("<br />"), $results['Description']), '<br />'), '<br><a>') : '';

$paragraphs = array_filter(explode("<br />", $description));

但这会删除所有换行符。我需要在字符串中保留换行符，但只想做 1 个换行符并删除所有其他换行符。这个怎么做？

注意：我使用的是 strip_tags 因为我只想在字符串中允许<br>和<a>标签。$description

Answer 1

您可能想先尝试用行尾 ( PHP_EOL) 爆炸，去掉除<a>, then array_filter(),implode()和之外的所有内容trim()：

$str    =   'This is paragraph 1<br>

This is paragraph 2<br /><br>



This is paragraph 3
This is paragraph 4


This is paragraph 5<br/>
This is paragraph 6


This is paragraph 7<br />';

$str    =   trim(implode('<br />'.PHP_EOL,array_filter(explode(PHP_EOL,strip_tags($str,'<a>')))));

echo $str;

给你：

This is paragraph 1<br />
This is paragraph 2<br />
This is paragraph 3<br />
This is paragraph 4<br />
This is paragraph 5<br />
This is paragraph 6<br />
This is paragraph 7

---

你的第二种情况：

$str    =   'This is paragraph 1<br>

This is paragraph 2<br /><br>



This is paragraph 3
This is paragraph 4


This is paragraph 5<br/>This is paragraph 5
This is paragraph 6


This is paragraph 7<br />';

# Explode on line breaks and remove empty lines
$exp    =   array_filter(explode(PHP_EOL,$str));
# Loop array and filter the lines
$new    =   array_map(function($v) {
                return strip_tags(trim($v,'<br>,<br />,<br/>'),'<a><br>');
            },$exp);
# Implode the array back
echo implode('<br />'.PHP_EOL,$new);

给你：

This is paragraph 1<br />
This is paragraph 2<br />
This is paragraph 3<br />
This is paragraph 4<br />
This is paragraph 5<br/>This is paragraph 5<br />
This is paragraph 6<br />
This is paragraph 7