What Interface Methods are useful for?

[paciox]

1 Forced cast:

Nonsense. Who inherits interface should be able to call. It has to implement every member of base interface so it can safely call that method without that extra cast

2.Parametrization
This is even more ridiculous

You have to write a ton of extra code.
Just let Roslyn or your boilerplate code generation to handle the fact that variables need to be initialized and used as parameters.
It should really be like this:

3. The use of access modifiers here doesn't make any sense?
   

Ehm no????
Interface require you to implement methods.
You could just let people override it with their own implementation. Protected is not needed?????

When one overrides base interface method it will call the inheriting class method, else the interface one.

This has to be the most useless thing ever

Calling the static method through the interface it's the same exact thing as doing any other utility static class.....
You can't do anything with it as you have to give an instance to use properties inside it and interface can't have any so everything is passed as a parameter and therefore useless. Any static class can do the same stuff without this convolute interfaces workaround

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• ID: 54cebe71-9575-ed30-b6b8-1f6222061961
• Version Independent ID: ecda34c3-a5b7-8b8c-baa4-4ea741478e5f
• Content: Safely update interfaces using default interface methods in C#
• Content Source: docs/csharp/whats-new/tutorials/default-interface-methods-versions.md
• Product: dotnet-csharp
• Technology: csharp-advanced-concepts
• GitHub Login: @BillWagner
• Microsoft Alias: wiwagn

[BillWagner]

Hi @paciox

I'll keep this open to evaluate when I next update this tutorial.

Your comments are correct for most interface definitions, where the interface doesn't include default members. Adding default interface members adds some benefits, but at the cost of increased complexity. That complexity comes in more complicated overload resolution, static helper methods and such.

I look at how to make that more clear in the next iteration.

[paciox]

Hi @paciox

I'll keep this open to evaluate when I next update this tutorial.

Your comments are correct for most interface definitions, where the interface doesn't include default members. Adding default interface members adds some benefits, but at the cost of increased complexity. That complexity comes in more complicated overload resolution, static helper methods and such.

I look at how to make that more clear in the next iteration.

@BillWagner
Hello,
I don't really see how my comments don't relate to interfaces with default implementations.
It looks more like a problem of bad design of the whole thing that makes it mostly useless or forces you to do extra code for a small benefit or for something that looks like more an overhead than a benefit.

How is beneficial to define everything in base interface then needing to cast it to get those methods?

All my observations look pertinent to an interface with default methods