$re = '/id="(.*)"/mU';
$str = ' <property id="leftLogoURL" labelText="Override Left Logo URL" dataType="string" defaultValue=""></property>
<property id="rightLogoURL" labelText="Override Right Logo URL" dataType="string" defaultValue=""></property>
<property id="title" labelText="Override Group Title" dataType="string" defaultValue=""></property>
<property id="description" labelText="Override Group Description" dataType="string" rows="2" defaultValue=""></property>
<property id="underDescription" labelText="HTML Under Description" dataType="html" rows="5" defaultValue=""></property>
<property id="button1state" labelText="Button 1 Display Mode" dataType="string" defaultValue="Standard">
<propertyValue value="Automatic" labelText="Automatic" propertiesToHide="button1label,button1url" propertiesToShow="" />
<propertyValue value="Overriden" labelText="Overriden" propertiesToHide="" propertiesToShow="button1label,button1url" />
<propertyValue value="Disabled" labelText="Disabled" propertiesToHide="button1label,button1url" propertiesToShow="" />
</property>
<property id="button1label" labelText="Button 1 Label" dataType="string" defaultValue=""></property>
<property id="button1url" labelText="Button 1 URL" dataType="string" defaultValue=""></property>
<property id="button2state" labelText="Button 2 Display Mode" dataType="string" defaultValue="Standard">
<propertyValue value="Automatic" labelText="Automatic" propertiesToHide="button2label,button2url" propertiesToShow="" />
<propertyValue value="Overriden" labelText="Overriden" propertiesToHide="" propertiesToShow="button2label,button2url" />
<propertyValue value="Disabled" labelText="Disabled" propertiesToHide="button2label,button2url" propertiesToShow="" />
</property>
<property id="button2label" labelText="Button 2 Label" dataType="string" defaultValue=""></property>
<property id="button2url" labelText="Button 2 URL" dataType="string" defaultValue=""></property>
<property id="button3state" labelText="Button 3 Display Mode" dataType="string" defaultValue="Standard">
<propertyValue value="Automatic" labelText="Automatic" propertiesToHide="button3label,button3url" propertiesToShow="" />
<propertyValue value="Overriden" labelText="Overriden" propertiesToHide="" propertiesToShow="button3label,button3url" />
<propertyValue value="Disabled" labelText="Disabled" propertiesToHide="button3label,button3url" propertiesToShow="" />
</property>
<property id="button3label" labelText="Button 3 Label" dataType="string" defaultValue=""></property>
<property id="button3url" labelText="Button 3 URL" dataType="string" defaultValue=""></property>
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php