title: Add hours to datetime in PHP
body: <p>I got a variable named <code>$transactiontime</code>. I want to add 6 hours to that variable. But I need to exclude the time between 12.00AM and 6.00AM. </p>
  
  <p>For example,
  I made a transaction at <code>1/1/2016 11.00PM</code>. After adding 6 hours, the output should be <code>2/1/2016 11.00AM</code>. </p>
  
  <p>How do I do this? Thank you</p>