default-interface-member

问题 If I have a default interface method like this: public interface IGreeter { void SayHello(string name) => System.Console.WriteLine($"Hello {name}!"); } Can I have my concrete implementation call that default method? public class HappyGreeter : IGreeter { public void SayHello(string name) { // what can I put here to call the default method? System.Console.WriteLine("I hope you're doing great!!"); } } So that calling: var greeter = new HappyGreeter() as IGreeter; greeter.SayHello("Pippy");

问题 If I have a default interface method like this: public interface IGreeter { void SayHello(string name) => System.Console.WriteLine($"Hello {name}!"); } Can I have my concrete implementation call that default method? public class HappyGreeter : IGreeter { public void SayHello(string name) { // what can I put here to call the default method? System.Console.WriteLine("I hope you're doing great!!"); } } So that calling: var greeter = new HappyGreeter() as IGreeter; greeter.SayHello("Pippy");

问题 Given that an auto property compiles to a get_method, a set_method and a private variable and since C# 8 is introducing default interface methods Can properties in Interfaces have default implementations? Especially a get only property? 回答1: Yes. Auto properties aren't a special type of property. They are a convenience feature that generates the code needed to store property values in a backing field. You can specify a default implementation for properties, both for getters and setters. You

问题 Given that an auto property compiles to a get_method, a set_method and a private variable and since C# 8 is introducing default interface methods Can properties in Interfaces have default implementations? Especially a get only property? 回答1: Yes. Auto properties aren't a special type of property. They are a convenience feature that generates the code needed to store property values in a backing field. You can specify a default implementation for properties, both for getters and setters. You

问题 This question already has answers here : Default Interface Methods. What is deep meaningful difference now, between abstract class and interface? [closed] (6 answers) Closed 10 months ago . C# 8.0 has introduced a new language feature – default implementations of interface members. public interface IRobot { void Talk(string message) { Debug.WriteLine(message); } } The new default interface implementations provides the elements of the traits language. However is is also blurring the line

问题 This question already has answers here : Default Interface Methods. What is deep meaningful difference now, between abstract class and interface? [closed] (6 answers) Closed 10 months ago . C# 8.0 has introduced a new language feature – default implementations of interface members. public interface IRobot { void Talk(string message) { Debug.WriteLine(message); } } The new default interface implementations provides the elements of the traits language. However is is also blurring the line

问题 There is currently little documentation surrounding the limitations of events with the new C#8 default interface implementations (traits). I am particularly confused with the spec proposal. Not only is the example given invalid C# (the "override" event is missing an identifier), but implementing any of these in C#8 (VS2019, .NET Core 3.0) returns a host of compiler exceptions. In addition, the release notes for C#8 don't make any mention of events for interface traits. As I continued to try

问题 C# 8.0 has a new feature that lets you add a default implementation to a method on an interface. Either I'm doing something wrong or this feature doesn't work as advertised. (I'm guessing it's the former.) I created a new .NET Core 3.1 console app with the following code: using System; namespace ConsoleApp1 { class Program { static void Main(string[] args) { var xxx = new MyClass { MyInt = 5 }; Console.WriteLine(xxx.GetItNow()); } } public interface ITest { int MyInt { get; set; } int

问题 Why is the behavior of Default Interface Methods changed in C# 8? In the past the following code (When the Default interface methods was demo not released): interface IDefaultInterfaceMethod { // By default, this method will be virtual, and the virtual keyword can be here used! virtual void DefaultMethod() { Console.WriteLine("I am a default method in the interface!"); } } interface IOverrideDefaultInterfaceMethod : IDefaultInterfaceMethod { void IDefaultInterfaceMethod.DefaultMethod() {

问题 Consider the code: class ChildClass : BaseClass { public void Method1() {} //some other method } abstract class BaseClass : IChildInterface { public virtual //<- If we add virtual so that this method can be overridden by ChildClass, we get StackOverflowException and DoWork() implementation in IChildInterface is never called. void DoWork() { //base class specific implmentation ((IChildInterface)this).DoWork(); //call into default implementation provided by IChildInterface } } interface