Specific regex function
<p>I have a database with member ID values. (always 8 digits long)
If member is on the pay list there is a "SI" prefix added to the ID.</p>

<p>For example: </p>

<pre><code>John: 12345678

Jack: SI87654321
</code></pre>

<p>Now i would like to write a function which checks if there is "SI" at the beginning of the number. (Some kind of regular expression which extracts the "SI" from the number)</p>

<p>If yes -> return ID number (without SI), YES radio button is checked. (checked="checked")</p>

<p>If not -> return ID number, NO radio button is checked. (checked="checked")</p>

<p>example:</p>

<p>PHP:</p>

<pre><code>$ID = get from database (for example: SI12345678)

function check () {return $pureNumber}
</code></pre>

<p>HTML:</p>

<pre><code>&lt;body&gt;
&lt;?php echo $pureNumber ?&gt;&lt;br/&gt;
&lt;label for="dz1"&gt;&lt;input type="radio" value="SI" name="davzav" id="dz1"/&gt;YES(SI)&lt;/label&gt;
&lt;label for="dz2"&gt;&lt;input type="radio" value="" name="davzav" id="dz1"/&gt;NO&lt;/label&gt;
&lt;/body&gt;
</code></pre>

<p>Thanks for your help</p>
