I use ProtoBuf to serialize class which is create开发者_运维技巧d at runtime using Activator.CreateInstance. Unfortunately Serializer.Deserialize method gives error "Type is not expected, and no contract can be inferred: System.Object". Any hint how to solve this.
var converterName = "Passing class name as string"
var type = Type.GetType(converterName);
var yourObject = Activator.CreateInstance(type)
if (yourObject != null)
{
FillRequest(Request.Params, yourObject);
var com = new CommunicationLayer();
yourObject = com.Submit(yourObject);
FillResponse(yourObject);
}
public class CommunicationLayer
{
public T Submit<T>(T engine)
{
<code skip>
Serializer.Serialize(stream, engine); //Works fine
<code skip>
engine = Serializer.Deserialize<T>(stream); //Gives error
<code skip>
}
}
I have choose to create and cast class at runtime from string because converterName variable parameter is passed in ASP.NET app and such classes will be about 100. Yes, I could replace the whole code with 100 If's
If converterName=="MyClass1"
{
var yourObject = new MyClass1();
FillRequest(Request.Params, yourObject);
var com = new CommunicationLayer();
yourObject = com.Submit(yourObject);
FillResponse(yourObject);
}
Else
If converterName=="MyClass2"
{
var yourObject = new MyClass2();
FillRequest(Request.Params, yourObject);
var com = new CommunicationLayer();
yourObject = com.Submit(yourObject);
FillResponse(yourObject);
}
Else
....
but I would like to have less code if possible.
That is because the generic method is inferring T=object.
There is a non-generic API intended for this scenario; look at Serializer.NonGeneric.*
Or in v2, everything under TypeModel/RuntimeTypeModel (where all the "real" code now is) is also non-generic throughout.
If you are doing this lots, I recommend using v2. In v1 the generic code is the "primary", with the non-generic code using reflection to shim into the generic code via MakeGenericMethod()
(relatively expensive). In v2 this is reversed: the non-generic code is the "primary", and the generic methods shim into the non-generic API via typeof(T)
.
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