I want to add some method in class that i define as a 'DataContract' class.
I need that the client will call those method in some cases.
Is it possible?
How can i do it ?
Thanks for any help.
If you mean that you want to add a service call to a DataContract then that is not possible. If you want to add some helper methods to the data contract and you want to make those available to the client as well then you can do that if you are also in charge of the client code or you are willing to share the library containing the data contract class with the clients.
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I have been assigned a task to create a WCF service which able to insert or fetch record. I was provided with one DLL, with the help of that I have to create. I am unable to see any method name not it's content. I downloaded one application which decompiled the assembly. Now I am able to see content of it. There are 2 class, one class contain properties (which accesses through get and set method) another class contain method which add record and fetch record.
How to create WCF service from that? I have already created lot of WCF service before that. In that case I have created cs file that in that created class who have properties(get,set) given name to class as datacontract and member as datamember. In service one class which implement interface. In interface just declare method and in interface define that method where I do inert/serach code and consumer application creating instance of service class and calling that method. But how to do in this situation?
You should be able to create a WCF service that wraps the provided DLL.
Create the ServiceContract (interface) with the methods you want.
Create the service that implements the contract, and add a reference to the provided DLL. In the service implementation, you can then call the methods from the provided DLL that you need.
You can also create DataContracts as needed for returning the data (or passing data in).
Essentially, it's exactly the same as the previous WCF services you've created, except that the actual functionality is in a separate assembly (DLL) that you reference, rather than being in the service implementation itself.
I have a WCF method which takes an argument that is a custom class, say,
void MyWCFMethod(MyCustomClass MethodArgument)
In the above, MyCustomClass has a number of constructor overloads. The service has a reference to the class but not the client. I want to allow the client to use the other overloads but the default constructor is the only one that seems to be allowed. Is there a way to do this?
You can certainly do this, but I think it is important to know why the Data Transfer Objects (DTOs) do not expose logic over the service reference.
The WSDL\XSD metadata that is used in order to generate the client proxy to access the WCF Service only describes the web service by the operations exposed and the datatypes exchanged.
Specifically, XSD only describes the structure of your DTOs and not the logic - that is why there is only the default constructor and public properties/fields available on the client proxy.
So the solution is to put all of your custom classes exchanged between the client and service in a separate shared library. This way both sides of the wire have access to the additional logic (like your parameterized constructors) that you could not obtain via WSDL\XSD.
I guess - no!
As I understand MyCustomClass is data contract and marked by [DataContract] attribute.
So WCF runtime will use DataContractSerializer (by default) to deserialize data from received message to the instance of object.
So where can DataContractSerializer get additional parameters for your specific constructors?
Instance of data contract must have public parameter-less constructor to be instantiated.
But maybe you can write own serializer (but keep in mind that DataContractSerializer cannot be inherited)... and provide additional data to constructor. But if you can get that information somewhere just do it in public parameter-less constructor of your data contract.
So I guess you are doing something wrong. Try to specify what is the goal to pass data in constructor in your case. Maybe your app can use some another solution.
I would like to declare an interface in my Web Service layer and then have the caller create objects of this interface type via proxy and use them to call the service methods.
However, when I decorate the interface with DataContract attribute, I get an error saying this attribute can only be applied to class, struct and enum. I don't think that ServiceContract attribute makes sense, as the interface I am trying to expose is used only for data transfer purposes. I also noticed that when the interface was decorated with ServiceContract, it wasn't displayed in the proxy class created.
What is the best practice to go about this?
You cannot do that. "DataContract" interface cannot be exposed as part of metadata. Also even if you share the interface (in assembly) your clients will not be able to send their implementation back to your service because receiving side needs real type for deserialized instance.
The service contract is used on the interface, that is the name of the services. The data contract is used on the class, the data that you are sending over.
ServiceContract on the interface
OperationContract on the methods
DataContract on Class
DataMember on properties
See: http://msdn.microsoft.com/en-us/magazine/cc163647.aspx
I have a WCF web service that implements a parameter List<ICustomObject>. In the generated client code, the parameter is List<Object>?!? How can I make it accept the List<ICustomObject>, as an interface, or do I have to use a concrete class? I have the concrete class marked as [KnowType] and [Serializable]
You should use concrete class, because you should set DataMember and DataContract for it to serilize it, and with interface you can't do this.
WCF works with anything that is expressible in XML schema - interfaces per se are not.
You need to define your lists to be lists of concrete types - otherwise the client will not be able to know what to do with the list and will fall back to a List<Object>.
I am just curious to know that what is ClientBase class in WCF, and how can i use it.
I surfed the internet and i found that this class is used to create proxies to call service methods , but no example.
Please anyone explain it with example , it will help me undestand this class...
It's the base class for your client proxies being generated by either "Add Service Reference", the svcutil.exe command line utility, or by your custom code if you don't want to use any of those methods.
It's a generic type that takes the generated client-copy of the service contract as its type parameter.
It can be extended, if you wish to do so - e.g. see IDesign's download page for a few samples of what can be done, things like:
AsyncClientBase for safe asynchronous calls
HeaderClientBase for simplified support of custom headers in your messages
Marc
It's there for autogenerated proxies which are created when service references are added to your project, not really for your own use.