C# DateTimeOffset formatting to a certain format

Question

Is there any reference where I could find out how I can create a format for the DateTimeOffset that would enable me to produce a string like this?

2016-10-01T06:00:00.000000+02:00

I have a DateTimeOffset that I can work with, but I'm not sure how I could format it to produce the above string representation?

Answer 1

What you want is an ISO 8601-standardized combined Date and Time string.

The "o" format string provides you with just that:

DateTimeOffset dto = new DateTimeOffset(DateTime.Now);
string iso8601date = dto.ToString("o")

Answer 2

The "O" or "o" standard format specifier corresponds to the yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'fffffffK custom format string for DateTime values and to the yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'fffffffzzz custom format string for DateTimeOffset values.

DateTime lDat = new DateTime(2009, 6, 15, 13, 45, 30, DateTimeKind.Local);

Console.WriteLine("{0} ({1}) --> {0:O}\n", lDat, lDat.Kind);
// 6/15/2009 1:45:30 PM (Local) --> 2009-06-15T13:45:30.0000000-07:00 

DateTimeOffset dto = new DateTimeOffset(lDat);
Console.WriteLine("{0} --> {0:O}", dto);
// 6/15/2009 1:45:30 PM -07:00 --> 2009-06-15T13:45:30.0000000-07:00    

Reference: https://msdn.microsoft.com/en-us/library/az4se3k1%28v=vs.110%29.aspx#Roundtrip