Using expression tree call a method with the same name on 2 unrelated classes

Question

Suppose I have a base class like the following

public abstract class BaseHelloWorld<T> where T : BaseEntity
{
    public abstract IEnumerable<T> DoSomething();
}

and another like

public class BaseEntity
{
    public abstract void DoSomethingInPayload();
}

Then I have 4 classes like:

public class Payload1 : BaseEntity
{
    public override void DoSomethingInPayload()
    {
        Console.Write("Hello world");
    }
}

public class Class1 : BaseHelloWorld<Payload1>
{
    public override IEnumerable<Payload1> DoSomething()
    {
        return new List<Payload1> {  };
    }
}   

public class Payload2 : BaseEntity
{
    public override void DoSomethingInPayload()
    {
        Console.Write("Goodbye world");
    }
}

public class Class2 : BaseHelloWorld<Payload2>
{
    public override IEnumerable<Payload2> DoSomething()
    {
        return new List<Payload2>() { };
    }
}

Although I have shown code here, suppose these where third party libraries that I don't have code for and I want to extend them. What I want to do is to be able to create a single extension method that will allow me to call the DoSomethingInPayload() method on the payload class similar to

public static void CallDoSomething<T>(this BaseHelloWorld<T> theClass) where T: BaseEntity
{
    theClass.DoSomethingInPayload();
}

Obviously this will not work so I started looking at expression trees. My reading suggests this is possible to do with expression trees but I cant figure it out. After hours of trying and getting nowhere I am unsure if my theory is correct. Therefore could you please tell me:

A) Is it possible to do this with expression trees B) If so how would I do it?

Thanks in advance

Answer 1

Your own example is not working because T is a different type in the input and return parameters.

Indeed, as @AleksAdreev mentioned, you could simply try:

public static IEnumerable<T> CallDoSomething<T>(this BaseHelloWorld<T> theClass)
{
    return theClass.DoSomething();
}

Which can then be called as follows:

var someClass = new Class2();
var someResult = someClass.CallDoSomething();