title: Date to milliseconds in PHP
body: <p>It maybe the simplest question but I'm struggling with this. I want to get the current time to millisecond for example <code>2016-03-04 11:57:00,00</code> without separators <code>2016030411570000</code></p>
  
  <p>I've tried this <code>date("YmdHisu")</code> but it returns time to microseconds.</p>