Ignoring symbols in PHP
<p>Suppose I have this code:</p>

<pre><code>&lt;form method="POST"&gt;
&lt;input type="text" name="expression"&gt;
&lt;input type="submit" name="submitexpression"&gt;
&lt;/form&gt;

&lt;?php
if(isset($_POST['submitexpression']))
{
$getexpression = $_POST['expression'];

?&gt;
</code></pre>

<p>If my input <code>$getexpression</code> value is: <code>((xyz))</code>, how do I ignore the parenthesis so that when I use <code>strlen</code> it only gives a value of 3 not 7?</p>