title: Increment php array with key value pairs in a loop
body: <p>How do I increment(add more values) to an array with key value pairs in a loop.</p>
  
  <pre><code>$field['choices'] = array(
     'custom' =&gt; 'My Custom Choice'
   );
  </code></pre>
  
  <p>Let's says I want to add three more choices from another array?</p>
  
  <p>Output I want to achieve:</p>
  
  <pre><code>$field['choices'] = array(
    'custom1' =&gt; 'My Custom Choice1'
    'custom2' =&gt; 'My Custom Choice2'
    'custom3' =&gt; 'My Custom Choice3'
    'custom4' =&gt; 'My Custom Choice4'
  );
  </code></pre>