正则表达式 - 如何重复正则表达式代码

I have on the site something like this:

 <div class="latestItemIntroText">

        <div class="itemLinks">
            <div class="share">Share</div>
            <div class="dummy-div"></div>

            <div class="addthis_sharing_toolbox"></div>

        </div>
     Lorem ipsum <br /><br />
     Lorem ipsum <br /><br />
     Lorem ipsum <br /><br />
     Lorem ipsum <br /><br />

 </div>

I need to have this text Lorem ipsum only. I tryed to do this regex code like this:

</div>([\s?]+[^<]+[<br?/?>]*[^<]+[<br?/?>]*[^<]+[<br?/?>]*[^<]+)</div>

I saw that this part I repeat many times :

[^<]+[<br?/?>]* --> because I don't know how many times there will be br with lorem pisum, maybe one, maybe 10 times... is there a possibility to short this regex?

Using Regex for HTML String is not a good approach, instead use DOMDocument for this.

Try this code snippet here

<?php
ini_set('display_errors', 1);
$string = <<<HTML
<div class="latestItemIntroText">

        <div class="itemLinks">
            <div class="share">Share</div>
            <div class="dummy-div"></div>

            <div class="addthis_sharing_toolbox"></div>

        </div>
     Lorem ipsum <br /><br />
     Lorem ipsum <br /><br />
     Lorem ipsum <br /><br />
     Lorem ipsum <br /><br />

 </div>
HTML;

$domDocument = new DOMDocument();
$domDocument->loadHTML($string);

$domXPath = new DOMXPath($domDocument);
$results = $domXPath->query('//div[@class="itemLinks"]');
$toRemove[]=$results->item(0);
foreach($toRemove as $removal)
{
    $removal->parentNode->removeChild($removal);
}
$results = $domXPath->query('//div[@class="latestItemIntroText"]');
print_r($results->item(0)->textContent);

This simpler regex does work for your input. All the usual caveats about the million different ways this would break do apply.

^(?!.*(?:<div|</div>))(.+?)(?=<br\s?/>|$)

Look ahead to not see any div tags, via negative lookahead.
reluctantly capture text up to a <br/> or EOL, via positive lookahead.

https://regex101.com/r/ePaFrp/4/