형식이 특정 일반 인터페이스 형식을 구현하는지 확인하는 방법

형식이 특정 일반 인터페이스 형식을 구현하는지 확인하는 방법

---

다음 유형 정의를 가정하십시오.

public interface IFoo<T> : IBar<T> {}
public class Foo<T> : IFoo<T> {}

맹 글링 된 형식 만 사용할 수있는 경우 형식 Foo이 일반 인터페이스를 구현 하는지 여부를 어떻게 알 IBar<T>수 있습니까?

---

TcK의 답변을 사용하여 다음 LINQ 쿼리로 수행 할 수도 있습니다.

bool isBar = foo.GetType().GetInterfaces().Any(x =>
  x.IsGenericType &&
  x.GetGenericTypeDefinition() == typeof(IBar<>));

---

상속 트리를 살펴보고 트리에서 각 클래스의 모든 인터페이스를 찾아 인터페이스가 일반 인지 여부typeof(IBar<>) 를 호출 한 결과 와 비교 해야합니다 . 확실히 조금 아 ful니다.Type.GetGenericTypeDefinition

참조 이 대답 하고 이러한 것들을 더 많은 정보와 코드를.

---

public interface IFoo<T> : IBar<T> {}
public class Foo : IFoo<Foo> {}

var implementedInterfaces = typeof( Foo ).GetInterfaces();
foreach( var interfaceType in implementedInterfaces ) {
    if ( false == interfaceType.IsGeneric ) { continue; }
    var genericType = interfaceType.GetGenericTypeDefinition();
    if ( genericType == typeof( IFoo<> ) ) {
        // do something !
        break;
    }
}

---

헬퍼 메소드 확장

public static bool Implements<I>(this Type type, I @interface) where I : class
{
    if(((@interface as Type)==null) || !(@interface as Type).IsInterface)
        throw new ArgumentException("Only interfaces can be 'implemented'.");

    return (@interface as Type).IsAssignableFrom(type);
}

사용법 예 :

var testObject = new Dictionary<int, object>();
result = testObject.GetType().Implements(typeof(IDictionary<int, object>)); // true!

---

약간 간단한 버전의 @GenericProgrammers 확장 방법을 사용하고 있습니다.

public static bool Implements<TInterface>(this Type type) where TInterface : class {
    var interfaceType = typeof(TInterface);

    if (!interfaceType.IsInterface)
        throw new InvalidOperationException("Only interfaces can be implemented.");

    return (interfaceType.IsAssignableFrom(type));
}

용법:

    if (!featureType.Implements<IFeature>())
        throw new InvalidCastException();

---

You have to check against a constructed type of the generic interface.

You will have to do something like this:

foo is IBar<String>

because IBar<String> represents that constructed type. The reason you have to do this is because if T is undefined in your check, the compiler doesn't know if you mean IBar<Int32> or IBar<SomethingElse>.

---

To tackle the type system completely, I think you need to handle recursion, e.g. IList<T> : ICollection<T> : IEnumerable<T>, without which you wouldn't know that IList<int> ultimately implements IEnumerable<>.

    /// <summary>Determines whether a type, like IList&lt;int&gt;, implements an open generic interface, like
    /// IEnumerable&lt;&gt;. Note that this only checks against *interfaces*.</summary>
    /// <param name="candidateType">The type to check.</param>
    /// <param name="openGenericInterfaceType">The open generic type which it may impelement</param>
    /// <returns>Whether the candidate type implements the open interface.</returns>
    public static bool ImplementsOpenGenericInterface(this Type candidateType, Type openGenericInterfaceType)
    {
        Contract.Requires(candidateType != null);
        Contract.Requires(openGenericInterfaceType != null);

        return
            candidateType.Equals(openGenericInterfaceType) ||
            (candidateType.IsGenericType && candidateType.GetGenericTypeDefinition().Equals(openGenericInterfaceType)) ||
            candidateType.GetInterfaces().Any(i => i.IsGenericType && i.ImplementsOpenGenericInterface(openGenericInterfaceType));

    }

---

First of all public class Foo : IFoo<T> {} does not compile because you need to specify a class instead of T, but assuming you do something like public class Foo : IFoo<SomeClass> {}

then if you do

Foo f = new Foo();
IBar<SomeClass> b = f as IBar<SomeClass>;

if(b != null)  //derives from IBar<>
    Blabla();

---

In case you wanted an extension method that would support generic base types as well as interfaces, I've expanded sduplooy's answer:

    public static bool InheritsFrom(this Type t1, Type t2)
    {
        if (null == t1 || null == t2)
            return false;

        if (null != t1.BaseType &&
            t1.BaseType.IsGenericType &&
            t1.BaseType.GetGenericTypeDefinition() == t2)
        {
            return true;
        }

        if (InheritsFrom(t1.BaseType, t2))
            return true;

        return
            (t2.IsAssignableFrom(t1) && t1 != t2)
            ||
            t1.GetInterfaces().Any(x =>
              x.IsGenericType &&
              x.GetGenericTypeDefinition() == t2);
    }

---

Method to check if the type inherits or implements a generic type:

   public static bool IsTheGenericType(this Type candidateType, Type genericType)
    {
        return
            candidateType != null && genericType != null &&
            (candidateType.IsGenericType && candidateType.GetGenericTypeDefinition() == genericType ||
             candidateType.GetInterfaces().Any(i => i.IsGenericType && i.GetGenericTypeDefinition() == genericType) ||
             candidateType.BaseType != null && candidateType.BaseType.IsTheGenericType(genericType));
    }

---

Try the following extension.

public static bool Implements(this Type @this, Type @interface)
{
    if (@this == null || @interface == null) return false;
    return @interface.GenericTypeArguments.Length>0
        ? @interface.IsAssignableFrom(@this)
        : @this.GetInterfaces().Any(c => c.Name == @interface.Name);
}

To test it. create

public interface IFoo { }
public interface IFoo<T> : IFoo { }
public interface IFoo<T, M> : IFoo<T> { }
public class Foo : IFoo { }
public class Foo<T> : IFoo { }
public class Foo<T, M> : IFoo<T> { }
public class FooInt : IFoo<int> { }
public class FooStringInt : IFoo<string, int> { }
public class Foo2 : Foo { }

and the test method

public void Test()
{
    Console.WriteLine(typeof(Foo).Implements(typeof(IFoo)));
    Console.WriteLine(typeof(FooInt).Implements(typeof(IFoo)));
    Console.WriteLine(typeof(FooInt).Implements(typeof(IFoo<>)));
    Console.WriteLine(typeof(FooInt).Implements(typeof(IFoo<int>)));
    Console.WriteLine(typeof(FooInt).Implements(typeof(IFoo<string>)));
    Console.WriteLine(typeof(FooInt).Implements(typeof(IFoo<,>)));
    Console.WriteLine(typeof(FooStringInt).Implements(typeof(IFoo<,>)));
    Console.WriteLine(typeof(FooStringInt).Implements(typeof(IFoo<string,int>)));
    Console.WriteLine(typeof(Foo<int,string>).Implements(typeof(IFoo<string>)));
 }

---

There shouldn't be anything wrong the following:

bool implementsGeneric = (anObject.Implements("IBar`1") != null);

For extra credit you could catch AmbiguousMatchException if you wanted to provide a specific generic-type-parameter with your IBar query.

참고URL : https://stackoverflow.com/questions/503263/how-to-determine-if-a-type-implements-a-specific-generic-interface-type