Indigo + GridView + Dataset interoperability

Dataset will definititely not be interoperable, and as a best practice, i would not recommend to use to pass data between layers if you need interoperability. Please note that datasets are good solutions when you control both sides of the system and you will never need to expose your service layer to other systems. Although, also pay attention to which kind of channels you're going to use, since serialized datasets are really expensive in bandwith, so the decision may be hard.

What you need are data contracts. You need to Type your data and normalize the contract for the results you're returning. Probably you will need a kind of Messaging Mapper pattern where you map your internal datasets to data contracts in the service layer.

asp.net 2.0 supports binding to custom structures, as i understand, so it shouldn't be a problem to implement this.

If you're new to data contracts, check this out. Maybe it helps.

HugoBatista at 2007-9-8 >

yep. That's a good question. It has to do with the way XmlFormatter serializes data contracts.

Imagine you have this:

[DataMember()]
public Collection<User> Team;

[DataMember()]
public IList<User> Friends;

[DataMember()]
public List<User> Family;

That would create this schema for the wire:

<xs:complexType name="User">
<xs:sequence>
<xs:element minOccurs="0" name="Team" nillable="true" type="tns:ArrayOfUser" />
<xs:element minOccurs="0" name="Friends" nillable="true" type="xs:anyType" />
<xs:element minOccurs="0" name="Family" nillable="true" type="tns:ArrayOfUser" />
</xs:sequence>
</xs:complexType>
<xs:element name="User" nillable="true" type="tns:User" />
<xs:complexType name="ArrayOfUser">
<xs:sequence>
<xs:element minOccurs="0" maxOccurs="unbounded" name="User" nillable="true" type="tns:User" />
</xs:sequence>
</xs:complexType>
So basically, in answer to your question: it depends of the way you specify it. If you use an IList or IDictionary, for example, it will generate an XmlAny.

Please remind.. any will be "interoperable".. but.. if won't be typed. so your consumer may not know what to send there, right ?

The greatness of this.. is that even the client is WCF, it doesn't know IList, since it will use the same public schema than other systems. So, in a case of an IList, WCF will generate an "object" type on the proxy.
I think there's a better way than what i do to check this out, but i can't find how. I use "SvcUtil AssemblyName" and then i check output.xsd . You find a better way, please let me know.

hope i helped..
regards

HugoBatista at 2007-9-8 >

thanks

HugoBatista at 2007-9-8 >