While working on a project I had to convert a date string to DateTime object. As the date value was coming from SharePoint it was a UTC date - "2010-01-01T00:00:00Z". So looking at the date value I expected that Convert.ToDateTime or DateTime.Parse will return me 1/1/2011 12:00:00 but to my surprise I was getting 12/31/2010 7:00:00 PM I quickly realized the mistake I was doing and searched MSDN and thanks to SPUtility class for the rescue. So convert UTC date string to a DateTime object use the following method to get the correct date -
objectDateString is object type with value "2010-01-01T00:00:00Z"
SPUtility.CreateSystemDateTimeFromXmlDataDateTimeFormat(objectDateString.ToString()) returns {1/1/2011 12:00:00 AM} System.DateTime
or the following will also return correct date -
Convert(objectDateString.ToString()).ToDateTime().ToUniversalTime()
using DateTime.Parse or Convert.ToDateTime I was getting wrong dates -
DateTime.Parse(objectDateString.ToString()) returns {12/31/2010 7:00:00 PM} System.DateTime
Convert.ToDateTime("2010-01-01T00:00:00Z") return {12/31/2010 7:00:00 PM}
Again lesson learned to treat DateTime values with respect. :)
For more information in this -
http://www.jamestsai.net/Blog/post/SPRegionalSettingsGlobalTimeZones-How-to-build-world-clock-get-time-zones-information-in-SharePoint.aspx
http://www.novolocus.com/2008/07/31/sharepoint-web-services-and-utc-time-fun-and-games/
