in PHP, how to remove specific class from html tag?

Question

given the following string in PHP:

$html = "<div>
<p><span class='test1 test2 test3'>text 1</span></p>
<p><span class='test1 test2'>text 2</span></p>
<p><span class='test1'>text 3</span></p>
<p><span class='test1 test3 test2'>text 4</span></p>
</div>";

I just want to either empty or remove any class that has "test2" in it, so the result would be this:

<div>
<p><span class=''>text 1</span></p>
<p><span class=''>text 2</span></p>
<p><span class='test1'>text 3</span></p>
<p><span class=''>text 4</span></p>
</div>

of if you're removing the element:

<div>
<p>text 1</p>
<p>text 2</p>
<p><span class='test1'>text 3</span></p>
<p>text 4</p>
</div>

I'm happy to use a regex expression or something like PHP Simple HTML DOM Parser, but I have no clue how to use it. And with regex, I know how to find the element, but not the specific attribute associated w/ it, especially if there are multiple attributes like my example above. Any ideas?

Answer 1

You can use any DOM Parser, iterate over every element. Check whether its class attribute contains test2 class (strpos()) if so then set empty string as a value for class attribute.

You can also use regular expressions to do that - much shorter way. Just find and replace (preg_replace()) using the following expression: #class=".*?test2.*?"#is

Answer 2

using the PHP Simple HTML DOM Parser

Updated and tested! You can get the simple_html_dom.php include from the above link or here.

for both cases:

include('../simple_html_dom.php');

$html = str_get_html("<div><p><span class='test1 test2 test3'>text 1</span></p>
<p><span class='test1 test2'>text 2</span></p>
<p><span class='test1'>text 3</span></p>
<p><span class='test1 test3 test2'>text 4</span></p></div>");

case 1:

foreach($html->find('span[class*="test2"]') as $e)
$e->class = '';

echo $html;

case 2:

foreach($html->find('span[class*="test2"]') as $e)
$e->parent()->innertext = $e->plaintext;

echo $html;

Answer 3

$notest2 = preg_replace(
         "/class\s*=\s*'[^\']*test2[^\']*'/", 
         "class=''", 
         $src);

C.