title: How rot13 on a string using PHP?
body: <p>I have a big php code that i want to encode and decode it manually.<br>
  My problem is that php code has many single quotes and double quotes inside and because of them i have errors while using <code>str_rot13()</code> function like below...<br>
  So what is the correct syntax and how can I use the function below for encode: </p>
  
  <pre><code>str_rot13 ('That php Code');
  </code></pre>
  
  <p>And how can i decode that encoded file? I couldn't find a reverse function!   </p>
  
  <p>thanks in advance</p>