<div>
If you dont want to replace the form-tag itself, only the id and name try using<br />
$html = &quot;&lt;form id=\&quot;form1\&quot; name=\&quot;form1\&quot; method=\&quot;post\&quot; action=\&quot;\&quot;&gt;&quot;;<br />
$html = preg_replace('/form(\d+)/s<wbr />i', 'f\1', $html);
</div>


If you dont want to replace the form-tag itself, only the id and name try using
$html = "<form id=\"form1\" name=\"form1\" method=\"post\" action=\"\">";
$html = preg_replace('/form(\d+)/si', 'f\1', $html);

<div>
What result are you getting and what were you expecting?
</div>


What result are you getting and what were you expecting?

<div>
<div class="content wysiwyg-content">
$html = &quot;&lt;form id=\&quot;form1\&quot; name=\&quot;form1\&quot; method=\&quot;post\&quot; action=\&quot;\&quot;&gt;&quot;;<br />
$html = preg_replace('/form/si', 'f1', $html);<br />
<br />
<br />
Anyone have any idea why this isnt working?
</div>
</div>


$html = "<form id=\"form1\" name=\"form1\" method=\"post\" action=\"\">";
$html = preg_replace('/form/si', 'f1', $html);


Anyone have any idea why this isnt working?

Simple regex not working

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