Type.GetInterfaces Method

Definition

When overridden in a derived class, gets all the interfaces implemented or inherited by the current Type.

public:
 abstract cli::array <Type ^> ^ GetInterfaces();
public abstract Type[] GetInterfaces ();
abstract member GetInterfaces : unit -> Type[]
Public MustOverride Function GetInterfaces () As Type()

Returns

Type[]

An array of Type objects representing all the interfaces implemented or inherited by the current Type.

-or-

An empty array of type Type, if no interfaces are implemented or inherited by the current Type.

Implements

Exceptions

A static initializer is invoked and throws an exception.

Examples

The following example gets the type of the specified class and displays all the interfaces that the type implements or inherits. To compile the Visual Basic example, use the following compiler commands:

vbc type_getinterfaces1.vb /r:System.Web.dll /r:System.dll

using namespace System;
using namespace System::Collections::Generic;

void main()
{
    Console::WriteLine("\r\nInterfaces implemented by Dictionary<int, String^>:\r\n");
     
    for each (Type^ tinterface in Dictionary<int, String^>::typeid->GetInterfaces())
    {
        Console::WriteLine(tinterface->ToString());
    }

    //Console::ReadLine()      // Uncomment this line for Visual Studio. 
}

/* This example produces output similar to the following:

Interfaces implemented by Dictionary<int, String^>:

System.Collections.Generic.IDictionary`2[System.Int32,System.String]
System.Collections.Generic.ICollection`1[System.Collections.Generic.KeyValuePair`2[System.Int32,System.String]]
System.Collections.Generic.IEnumerable`1[System.Collections.Generic.KeyValuePair`2[System.Int32,System.String]]
System.Collection.IEnumerable
System.Collection.IDictionary
System.Collection.ICollection
System.Runtime.Serialization.ISerializable
System.Runtime.Serialization.IDeserializationCallback
 */
using System;
using System.Collections.Generic;

public class Example
{
    static void Main()
    {
        Console.WriteLine("\r\nInterfaces implemented by Dictionary<int, string>:\r\n");

        foreach (Type tinterface in typeof(Dictionary<int, string>).GetInterfaces())
        {
            Console.WriteLine(tinterface.ToString());
        }

        //Console.ReadLine()      // Uncomment this line for Visual Studio.
    }
}

/* This example produces output similar to the following:

Interfaces implemented by Dictionary<int, string>:

System.Collections.Generic.IDictionary`2[System.Int32,System.String]
System.Collections.Generic.ICollection`1[System.Collections.Generic.KeyValuePair`2[System.Int32,System.String]]
System.Collections.Generic.IEnumerable`1[System.Collections.Generic.KeyValuePair`2[System.Int32,System.String]]
System.Collection.IEnumerable
System.Collection.IDictionary
System.Collection.ICollection
System.Runtime.Serialization.ISerializable
System.Runtime.Serialization.IDeserializationCallback
 */
open System.Collections.Generic

printfn "\nInterfaces implemented by Dictionary<int, string>:\n"

for tinterface in typeof<Dictionary<int, string>>.GetInterfaces() do
    printfn $"{tinterface}"

(* This example produces output similar to the following:

Interfaces implemented by Dictionary<int, string>:

System.Collections.Generic.IDictionary`2[System.Int32,System.String]
System.Collections.Generic.ICollection`1[System.Collections.Generic.KeyValuePair`2[System.Int32,System.String]]
System.Collections.Generic.IEnumerable`1[System.Collections.Generic.KeyValuePair`2[System.Int32,System.String]]
System.Collection.IEnumerable
System.Collection.IDictionary
System.Collection.ICollection
System.Runtime.Serialization.ISerializable
System.Runtime.Serialization.IDeserializationCallback
 *)
Imports System.Collections.Generic

Public Class Example

    Shared Sub Main()

        Console.WriteLine(vbCrLf & _
            "Interfaces implemented by Dictionary(Of Integer, String):" & vbCrLf)
        
        For Each tinterface As Type In GetType(Dictionary(Of Integer, String)).GetInterfaces()

            Console.WriteLine(tinterface.ToString())

        Next

        'Console.ReadLine()      ' Uncomment this line for Visual Studio. 
    End Sub
End Class

' This example produces output similar to the following:
'
'Interfaces implemented by Dictionary(Of Integer, String):
'System.Collections.Generic.IDictionary`2[System.Int32,System.String]
'System.Collections.Generic.ICollection`1[System.Collections.Generic.KeyValuePair`2[System.Int32,System.String]]
'System.Collections.Generic.IEnumerable`1[System.Collections.Generic.KeyValuePair`2[System.Int32,System.String]]
'System.Collection.IEnumerable
'System.Collection.IDictionary
'System.Collection.ICollection
'System.Runtime.Serialization.ISerializable
'System.Runtime.Serialization.IDeserializationCallback

Remarks

In .NET 6 and earlier versions, the GetInterfaces method does not return interfaces in a particular order, such as alphabetical or declaration order. Your code must not depend on the order in which interfaces are returned, because that order varies. However, starting with .NET 7, the ordering is deterministic based upon the metadata ordering in the assembly.

If the current Type represents a constructed generic type, this method returns the Type objects with the type parameters replaced by the appropriate type arguments.

If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the interface constraints and any interfaces inherited from class or interface constraints.

Applies to

See also