如何使用PHP正则表达式用单个span标签替换具有相同类名的多个span标签

Question

I have to replace all the span tags with the same class name to a single span tag using PHP regular expression. I got to know we can do this by using DOMDocument and also by using javascript/jQuery. Also i tried with the code below but its close.

[<span(.*)><strong>*](.*)<\/strong><\/span>

Below is the code I'm referring to.

<span class="c28"><strong><span class=
  "c28"><strong><span class="c28"><strong><span class=
  "c28"><strong><span class="c28"><strong><span class=
  "c28"><strong><span class="c28"><strong><span class=
  "c28"><strong><span class="c28"><strong><span class=
  "c28"><strong><span class="c28"><strong><span class=
  "c28"><strong><span class="c28"><strong><span class=
  "c28"><strong><span class="c28"><strong><span class=
  "c28"><strong><span class="c28"><strong><span class=
  "c28"><strong><span class="c28"><strong><span class=
  "c28"><strong>Sending text messages that include links,
  attachments and/or
  pictures.</strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span></strong></span>

I want the output like

<span class="c28"><strong>Sending text messages that include links, attachments and/or pictures.</strong></span>

Can anyone please help me with this regular expression. Thanks

Answer 1

In this case, you could make use of the fact that you are targeting a non-empty <strong> with text content - which means you can use this fairly simple pattern:

regex: .*?class="(\\w+)".*(<strong>[^<]+<\\/strong>).*

replace: <span class="$1">$2</span>

https://regex101.com/r/mtUBWx/2/

Answer 2

Nested strong s should be avoided. Also nested span s, regardless of their class names, which immediately come after the another demonstrate a misuse of HTML implementation. You may go with:

(</?\w+[^>]*>)(?1)*\1

Live demo

PHP code:

preg_replace('~(</?\w+[^>]*>)(?1)*\1~', '\\1', $string);