title: Finding the difference in MS between two dateTimes in XSLT 1.0
body: <p>I have an XML file which includes some dates with start and end points, like shown as follows:</p>
  
  <pre><code>&lt;events&gt;
      &lt;event&gt;
          &lt;start time="2018-10-20T10:11:36.465Z"/&gt;
          &lt;end time="2018-10-20T09:33:04.349Z"/&gt;
      &lt;/event&gt;
  &lt;/events&gt;
  </code></pre>
  
  <p>How to calculate the difference between these two date in millisecond (MS) ?</p>
  
  <p>I find something here from michael.hor257k : <a href="https://stackoverflow.com/questions/38604414/finding-the-difference-between-two-datetimes-in-xslt">Finding the difference between two dateTimes in XSLT</a> 
  but unfortunately, my level is too bad to re-use this one :(</p>