interface

问题 Looking at System.Collections.Generic.Dictionary<TKey, TValue> , it clearly implements ICollection<KeyValuePair<TKey, TValue>> , but doesn't have the required " void Add(KeyValuePair<TKey, TValue> item) " function. This can also be seen when trying to initialize a Dictionary like this: private const Dictionary<string, int> PropertyIDs = new Dictionary<string, int>() { new KeyValuePair<string,int>("muh", 2) }; which fails with No overload for method 'Add' takes '1' arguments Why is that so?

问题 I'm planning on making a program that interfaces with a UCI chess engine. I've been doing some research on it, but I want to get a little more information before I get more in depth with it. I was wondering if any of you could provide a few example "exchanges" between a UCI engine and a front-end program. I'm not really concerned with the practical interface code (like sending/receiving commands), that should be simple enough. I'm just trying to get some good examples of a small game and some

问题 I am having trouble with the concept of interfaces interacting with polymorphic types (or even polymorphic interfaces). I'm developing in C# and would appreciate answers staying close to this definition, although i think that still gives plenty of room for everyone to put forth an answer. Just as an example, let's say you want to make a program to paint things. You define an interface for the actor that Paints, and you define an interface for the subject which is painted, Furthermore you have

问题 This code: interface Config { int MAX_CONN = 20; } compiled and worked as I expected. It looks like this is the same as: interface Config { public static final int MAX_CONN = 20; } Is "public static final" redundant for a constant in a Java interface? Is this true for Java 1.1, 1.2, 1.3, 1.4,..., 1.8 or did it change in a Java release? 回答1: Variables declared in Interface are implicitly public static final . This is what JLS 9.3 says : Every field declaration in the body of an interface is

问题 This question already has answers here : Closed 7 years ago . Possible Duplicate: Interfaces: Why can't I seem to grasp them? Why would I want to use Interfaces? I think this question is repeated 1000 times and I'm sorry for asking again. I really looking for a plain simple answer why I explicitly need interface, or if you please explain something I can't achieve without Interface. If it is multiple inheritance then I would request you to give me one simple example through which I can

问题 Is contract to interface as object is to class? What is the need to differentiate identical things like this, from the code to the executing code? I sort of get the idea behind naming a class a class and the instantiated executing class an object, but overall, is that the only reason for these semi-redundant terms? 回答1: Not really. There are four terms here, so I'll go over each of them: Interface An interface is an abstract class (in languages like Java where there is no multiple inheritance

问题 This question already has answers here : What is the difference between an interface and abstract class? (34 answers) Closed 6 years ago . As the title states i want to know the difference between using the class like this public class Account { public string Username { get; set; } public string Password { get; set; } } and using and Interface like this public class Account : IAccount { public string Username { get; set; } public string Password { get; set; } } public interface IAccount {

问题 In the following code piece, trying to convert a nil interface to a pointer of something fails with the following error: interface conversion: interface is nil, not *main.Node type Nexter interface { Next() Nexter } type Node struct { next Nexter } func (n *Node) Next() Nexter {...} func main() { var p Nexter var n *Node fmt.Println(n == nil) // will print true n = p.(*Node) // will fail } Play link here: https://play.golang.org/p/2cgyfUStCI Why does this fail exactly? It's entirely possible

问题 Is there a way to write interface-based code (i.e. using interfaces rather than classes as the types accepted and passed around) in C# without giving up the use of things like implicit casts? Here's some sample code - there's been a lot removed, but these are the relevant portions. public class Game { public class VariantInfo { public string Language { get; set; } public string Variant { get; set; } } } And in ScrDictionary.cs, we have... public class ScrDictionary: IScrDictionary { public

问题 I need to be able to create an interface like you create in C# to enforce a group of classes to implement certain methods. Is this possible in objective c? 回答1: You can create a protocol. it would look something like this: in MyProtocol.h: @protocol MyProtocol -(void)myMethod; -(void)myMethod2; @end in MyClass.h #import "MyProtocol.h" @interface MyClass : NSObject<MyProtocol> @end If you want to receive objects of a given protocol, you can do so like this: id<MyProtocol> var; or NSObject