title: Convert null to string
body: <p>Is it possible to convert <code>null</code> to <code>string</code> with php?</p>
  
  <p>For instance,</p>
  
  <pre><code>$string = null;
  </code></pre>
  
  <p>to </p>
  
  <pre><code>$string = "null";
  </code></pre>