datetime with offset > local and utc

[chandy]

Hi,

I have a datetime+offset as a string and want to get two datetimes
from it; the local and UTC. So far I can only do it by splitting on
the + or - of the offset and creating a new date with and without the
offset. Is there a cleaner way, i.e., using System.DateTime etc. and
not resorting to string splitting? I had read about DateTimeOffset
which seems ideal but this is an ASP.Net 2.0 app and that seems to be
only in Framework 3.5

Chandy

 

[mpetrotta]

Hi,

I have a datetime+offset as a string and want to get two datetimes
from it; the local and UTC. So far I can only do it by splitting on
the + or - of the offset and creating a new date with and without the
offset. Is there a cleaner way, i.e., using System.DateTime etc. and
not resorting to string splitting? I had read about DateTimeOffset
which seems ideal but this is an ASP.Net 2.0 app and that seems to be
only in Framework 3.5

If the format of your date string is predictable, you can do thus:

string s = "2007-02-02 00:00 -8";
DateTime d = DateTime.ParseExact(s, "yyyy-dd-MM hh:mm z",
CultureInfo.CurrentCulture); // 'z' is the time zone offset specifier
Console.WriteLine(d.Kind); // prints "Local"
Console.WriteLine(d); // prints "2/2/2007 12:00:00 AM"
Console.WriteLine(d.ToUniversalTime()); // prints "2/1/2007 8:00:00
AM"

Look up "Custom DateTime Format Strings" in MSDN for more info.

Michael

 

[mpetrotta]

Console.WriteLine(d.Kind); // prints "Local"
Console.WriteLine(d); // prints "2/2/2007 12:00:00 AM"
Console.WriteLine(d.ToUniversalTime()); // prints "2/1/2007 8:00:00
AM"

Minor error: the output is actually:

Local
2/2/2007 12:00:00 AM
2/2/2007 8:00:00 AM

....as it should be.

 

[mpetrotta]

Minor error: the output is actually:

Local
2/2/2007 12:00:00 AM
2/2/2007 8:00:00 AM

...as it should be.

Ach. Too many replies to myself.

As I try it again, I see that a simple parse works fine:

string s = "2007-02-02 00:00 -8";
DateTime d = DateTime.Parse(s);
Console.WriteLine(d.Kind); // prints "Local"
Console.WriteLine(d); // prints "2/2/2007 12:00:00 AM"
Console.WriteLine(d.ToUniversalTime()); // prints "2/2/2007 8:00:00
AM"

Michael

 

[Peter Duniho]

Hi,

I have a datetime+offset as a string and want to get two datetimes
from it; the local and UTC. So far I can only do it by splitting on
the + or - of the offset and creating a new date with and without the
offset. Is there a cleaner way, i.e., using System.DateTime etc. and
not resorting to string splitting? I had read about DateTimeOffset
which seems ideal but this is an ASP.Net 2.0 app and that seems to be
only in Framework 3.5

How are you converting the strings now?

The Parse() and ParseExact() methods for DateTime include an overload
that takes a DateTimeStyles parameter. Using that parameter you can
specify the AdjustToUniversal style (flag), which will cause the
DateTime value formatted as a local time with offset to stored as a
universal time.

So, you can parse the string twice, once with the flag and once without
to get two different versions of the DateTime.

Pete