capture TimeZone of DateTime passed to web service?

[asanford]

I want to create a web service that allows the caller to pass a DateTime to
the web service (that is, create a web method such as void
MyWebMethod(DateTime dt).) However, I want to be able to capture the
TimeZone of the caller as well - but I don't want the interface to specify an
xs:string as the method argument - I want it to use an xs:dateTime type
argument.

Now, I know when a DateTime structure is serialized into XML it becomes an
xs:dateTime type, and it is always formatted using the full ISO 8601 format,
including the offset to UTC for the sending computer (such as
"2005-08-24T01:02:03+08:00", where the offset to UTC is +8 hours in this
example.) When the web service receives the call, the xs:dateTime is
automagically deserialized back into a DateTime structure (probably by the
framework internally calling DateTime.Parse()), which converts the string
into the correct local time using the receiving computer's TimeZone.

Is there (with attributes?) to get at the raw string that comes in with the
method call, for a primative type such as DateTime? I know I could change
the param type to string, but I want to let the caller know that they should
only pass dateTimes, not arbitrary strings. I tried using
XmlElementAttribute to specify the argument use xs:dateTime with a .Net type
of System.String, but it gives me an error.

Any ideas? Thanks!

[[MSFT]]

I think the best idea is to add a xs:string parameter or add a parameter
for TimeZone, these should be easy ways. Otherwise, you have to get the raw
soap message on server side and analyst the string like
"2005-08-24T01:02:03+08:00" to get TimeZone infomation. To do this, you may
need to use SoapExtension:

http://msdn.microsoft.com/library/de...us/cpref/html/
frlrfsystemwebservicesprotocolssoapextensionclasst opic.asp

Luke

[asanford]

Thanks for your reply, Luke. I have a couple follow-up questions:

1) Without using SoapExtensions, is there no other way to have the web
method interface & WSDL specify xs:dateTime, but have the element delivered
to the c# code as an xs:string? It seems that a string format would always
be possible, as that really is the native format the data is sent as. Is
there no attribute (like XmlElementAttribute) that can achieve this?

2) You mention adding a TimeZone parameter: could you elaborate on this
idea? I had been considering trying to have the caller send their
TimeZone.CurrentTimeZone object (which is serializable, and seems to
serialize the offset to UTC and the timezone string labels - such as "EST" -
but doesn't seem to serialize the daylightsavings info), but I thought I read
somewhere that a given PC can only have a TimeZone object that represents the
current local time zone, not another timezone. If I can fully utilize the
TimeZone object from another timezone, that would be perfect.

Or, maybe you were thinking more of some sort of globally-recognized
standard string timezone identifier? If so, how would I utilize that? I
have seen some third-party classes that might be able to make use of such a
string.

Thanks,
-A

"[MSFT]" wrote:

I think the best idea is to add a xs:string parameter or add a parameter
for TimeZone, these should be easy ways. Otherwise, you have to get the raw
soap message on server side and analyst the string like
"2005-08-24T01:02:03+08:00" to get TimeZone infomation. To do this, you may
need to use SoapExtension:

http://msdn.microsoft.com/library/de...us/cpref/html/
frlrfsystemwebservicesprotocolssoapextensionclasst opic.asp

Luke

[[MSFT]]

(1) I am afraid that there is no attribute which can be set on a parameter
in a web method.

(2) A TimeZone is just passed as a value, like a string or integer, it will
do nothing with TimeZone on the server. And you can pass a integer or a
string to the web server for client timezone, for example, "8" or "+8".

Luke