Question

let’s say I have a class defined in an assembly with:

public class BaseClass
{
    internal BaseClass()
    {
    }
}

And in another assembly, I would like to instanciate this class with :

BaseClass c = new BaseClass();

I get the CS0143 error.

Trying another way, I try to create a derived class of the first one :

public class DerivedClass : BaseClass
{
}

but same error.

The BaseClass is not sealed. How can I instantiate this class or a derived one? Of course, I can’t modify the BaseClass.

Answer 1

You’ll have to use reflection to get the internal constructor and invoke it:

var ci = typeof(BaseClass).GetConstructor(BindingFlags.Instance | BindingFlags.NonPublic, null, Type.EmptyTypes, null);
var instance = (BaseClass)ci.Invoke(new object[0]);

Since the existence of the constructor is only discovered at run-time, this approach will break if the constructor of BaseClass is changed or removed.