PHP在html页面上搜索某个html代码[重复]

I need search in html string this code:

 <a href="http://example.com" target="_blank" title="Site name"><img src="http://site.loc/images/banners/we_on.png" width="88" height="31" alt="Site name"></a>

How I can find this with regex?

I tried this:

$html = (string) $client->getBody(); //html content 

$verified = preg_match('/ <a href="http://example.com" target="_blank" 
title="Site name"><img src="http://site.loc/images/banners/we_on.png" 
 width="88" height="31" alt="Site name"></a>
  /', $html) ? true : false;

But I get error undefined expression. Maybe need check if on html I have a link and href of this link?

</div>