Is it possible to map C# object type in Slice?

[babaq]

I plan to expose a backend written in C# using ICE. Part of the planed API would be:

bool SetParam(string name, object value)
object GetParam(string name)

How to map the C# API to Slice?

A param can be variety of types. In protobuf, there is a Any type that fit my requirement, but i can't find a way to implement it in Slice.

[bernardnormier]

If your focus is C#, you may want to check out IceRPC.

In Ice 3.7 and prior releases, we support "object serialization" in C#, which allows you to use C# serialization to marshal any C# object into a sequence of bytes. See:
https://doc.zeroc.com/ice/3.7/the-slice-language/serializable-objects
https://doc.zeroc.com/ice/3.7/language-mappings/c-sharp-mapping/client-side-slice-to-c-sharp-mapping/serializable-objects-in-c-sharp

However, I would recommend against using this feature because:

• object serialization is deprecated in .NET (even removed in the latest .NET versions)
• we're dropping this feature in Ice 3.8.

In Ice - Slice, you can model "any" Slice type using the Value keyword - the base class for all Slice classes. You could convert your C# API into:

bool SetParam(string name, Value v);
Value GetParam(string name);

And then define a number of Slice classes that hold the various types you want to get/set with Get/SetParam:

class StringValue { string v; } // holds a string 
class ColorValue { Color v; }  // holds a Color enumerator
...

New Slice provides a more elegant and efficient solution: enum with fields

enum Shape {
    Circle(radius: uint32)
    Rectangle(width: uint32, length: uint32)
    Dot
}

It's nicer than Protobuf's Any type, and it could be better suited for your use-case.

[babaq]

@bernardnormier Thanks for the quick response.

Our current situation would be a C# Server(.NET Framework 4.8) and Python/C# Clients. So if i use IceRPC at server in Slice1 mode, Python client would be able to interop, right?

[bernardnormier]

Yes, IceRPC with Slice1 and the ice protocol interoperates with Ice except for a few uncommon situations (you use compression with Ice, or you use batch requests with Ice). For most applications, there is no interop issue.

However, IceRPC C# requires a recent .NET (.NET 8.0 or 9.0). It won't work with .NET Framework 4.8.

[babaq]

We will try ICE instead, because we are currently stuck with .NET Framework. Thanks.