title: Parse query string into an array
body: <p>How can I turn a <strong>string</strong> below into an <strong>array</strong>?</p>
  
  <pre><code>pg_id=2&amp;parent_id=2&amp;document&amp;video 
  </code></pre>
  
  <p>This is the array I am looking for,</p>
  
  <pre><code>array(
      'pg_id' =&gt; 2,
      'parent_id' =&gt; 2,
      'document' =&gt; ,
      'video' =&gt;
  )
  </code></pre>