title: find and replace image url source?
body: <p>I have an image without <code>class</code> and <code>id</code>, just <code>src</code> exists. I want to empty the <code>src</code> attribute.</p>
  
  <pre><code>&lt;td class="ms-vb" style="padding-bottom: 5px;"&gt;
      &lt;img alt="" src="/_layouts/images/square.gif"/&gt;
  &lt;td&gt;
  </code></pre>
  
  <p>to </p>
  
  <pre><code>&lt;td class="ms-vb" style="padding-bottom: 5px;"&gt;
      &lt;img alt="" src=""/&gt;
  &lt;/td&gt;
  </code></pre>
  
  <p>I need to find this image among several images in HTML. How to do that?</p>