microsoft.public.dotnet.framework.aspnet.webservices

Stan Yamane

7/15/2003 5:56:00 PM

Found a workaround that seems to work. Thanks.


>-----Original Message-----
>I'm trying to use a web service which sometimes returns
>objects which contain null members. However, when
>returning those objects, rather than just leaving those
>members out of the returned XML, it represents them with
>elements with xsi:nil attribute set to "true". (as
>apparently allowed in the SOAP 1.1 rules for encoding,
>section 5.1) [By default, .NET just leaves out elements
>when it wants to return null from a server.
>However, .NET can be made to replicate this behavior if
>you set the IsNullable flag on the XmlElementAttribute
>to "true" for each member you want to return as null]
>
>My problem is that when a generated .NET client receives
>this message, rather than unmarshalling it as null, it
>calls the default constructor of the object and returns
>that object to my client code.
>
>Example fragment:
>
>Normal .NET response:
><ReturnNullObjectInContainerResponse
>xmlns="http://tempuri.org/"><ReturnNullObjectInC...
>sult /></ReturnNullObjectInContainerResponse>
>
>..NET response w/ IsNullable=true [or from the server I
>need to connect to]:
><ReturnNullObjectInContainerResponse
>xmlns="http://tempuri.org/"><ReturnNullObjectInC...
>sult><TestObject
>xsi:nil="true"
/></ReturnNullObjectInContainerResult></Ret>urnNullObjectInContainerResponse>
>
>As I understand it, the xsi:nil attribute should cause
>the .NET runtime to create the container object and place
>a null object inside of it, just as not having the object
>should, but this doesn't seem to happen.
>
>Has anyone else run across this and found a workaround?
>
>I've tested this in .NET framework 1.1 and it still seems
>to be a problem.
>
>.
>