Format Conversion happening for date but don't know why?

I am facing a strange problem. At first, when i insert a record in XML containing a date property which is binded to a DatePicker in XAML. The Element is in this form 2011-01-22T00:00:00

Then there is a update page, which is filled with the values read from XML. I am reading date like this Date = DateTime.Parse(record.Element("Date").Value;

Now when i click update, and replace the date value like this record.Element("Date").Value = Date. The format Changes and Date element is like this 22-01-2开发者_如何学C011 00:00:00

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I found the reason for this format Conversion. Actually at first i am directly inserting the date into xml like this doc.Element("root").Add(new XElement("Date", dt))) but while updation, the date is first converted to string and then updated/added to XML.

Conclusion

• Direct Insertion of DateTime into XML has the SortableDateTimePattern (based on ISO 8601) using local time; with this format pattern, the formatting or parsing operation always uses the invariant culture
• While Insertion of DateTime.ToString() Converts the value of DateTime object to its equivalent string representation. (Overrides ValueType ..::.ToString ()()().)

Thank you all.