Adding generic object to generic list in C#

Question

I have class where the relevant part looks like

class C {
    void Method(SomeClass obj) {
        list.Add(obj);
    }
    List l         


        

Answer 1

I don't know anything about Java's ? construct, but I think the following most closely preserves your existing syntax while also matching your description.

    class SomeClass
    {
    }

    class C
    {
        void Add(SomeClass item)
        {
            Type type = typeof(SomeClass);
            if (!list.ContainsKey(type))
                list[type] = new List>();
            var l = (List>)list[type];
            l.Add(item);
        }

        public void Method(SomeClass obj)
        {
            Add(obj);
        }
        readonly Dictionary list = new Dictionary();
    }

test it with the following:

    class Program
    {
        static void Main(string[] args)
        {
            var c = new C();
            var sc1 = new SomeClass();
            var sc2 = new SomeClass();
            c.Method(sc1);
            c.Method(sc2);
            c.Method(sc1);
            c.Method(sc2);
        }
    }