C#

class SomeType
{
    public void Foo()
    {
        Console.WriteLine("SomeType.Foo");
    }
}

class AnotherType
{
    private SomeType someType = new SomeType();
}

class App
{
    static void Main()
    {
        AnotherType another = new AnotherType();
        string fieldName = "someType";

        FieldInfo fi = another.GetType().GetField(fieldName, BindingFlags.NonPublic | BindingFlags.Instance);
        object fieldValue = fi.GetValue(another);

        SomeType someType = fieldValue as SomeType;
        if(someType != null)
        {
            someType.Foo();
        }
    }
}

PIEBALDconsult wrote:

And chicks dig it