List all the classes that implement a specific interface

First create a class library, mydll2.dll, from the code below:

public interface IFace {}

public class ClassA : IFace {}

public class ClassB : IFace {}

public class ClassC : ClassA {}

public class ClassD : IFace {}

public class ClassE {}

Now create a console app from the following code and place the dll in the executable's folder:

using System;

using System.Reflection;

using System.Collections.Generic;

class Test

{

static Assembly assembly;

static void Main()

{

assembly = Assembly.LoadFrom("mydll2.dll");

IList list = GetAllImplementingTypes("IFace");

foreach(string typeName in list) Console.WriteLine(typeName);

Console.ReadKey();

}

static IList GetAllImplementingTypes(string interfaceName)

{

List list = new List();

foreach(Type t in assembly.GetTypes())

{

if (t.GetInterface(interfaceName) != null) list.Add(t.FullName);

}

return list;

}

}

The output should be:

ClassA

ClassB

ClassC
ClassD

Notice that ClassC is returned because it implements IFace by virtue of deriving from ClassA.

2 Replies

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Vulpes14y ago
Accepted answer
First create a class library, mydll2.dll, from the code below:

public interface IFace {}

public class ClassA : IFace {}

public class ClassB : IFace {}

public class ClassC : ClassA {}

public class ClassD : IFace {}

public class ClassE {}

Now create a console app from the following code and place the dll in the executable's folder:

using System;
using System.Reflection;
using System.Collections.Generic;

class Test
{
static Assembly assembly;

static void Main()
{
assembly = Assembly.LoadFrom("mydll2.dll");
IList list = GetAllImplementingTypes("IFace");
foreach(string typeName in list) Console.WriteLine(typeName);
Console.ReadKey();
}

static IList GetAllImplementingTypes(string interfaceName)
{
List list = new List();

foreach(Type t in assembly.GetTypes())
{
if (t.GetInterface(interfaceName) != null) list.Add(t.FullName);
}

return list;
}
}

The output should be:

ClassA
ClassB
ClassC
ClassD

Notice that ClassC is returned because it implements IFace by virtue of deriving from ClassA.
Akkiraju Ivaturi14y ago
Thanks for the code and it gives me answer to my question. Appreciate your time for this.