title: Parsing an ISO8601 date/time (including TimeZone) in Excel
body: <p>I need to parse an ISO8601 date/time format with an included timezone (from an external source) in Excel/VBA, to a normal Excel Date. As far as I can tell, Excel XP (which is what we're using) doesn't have a routine for that built-in, so I guess I'm looking at a custom VBA function for the parsing.</p>
  <p>ISO8601 datetimes look like one of these:</p>
  <pre class="lang-none prettyprint-override"><code>2011-01-01
  2011-01-01T12:00:00Z
  2011-01-01T12:00:00+05:00
  2011-01-01T12:00:00-05:00
  2011-01-01T12:00:00.05381+05:00
  </code></pre>