Is there a better alternative than this to 'switch on type'?

Question

Seeing as C# can\'t switch on a Type (which I gather wasn\'t added as a special case because is relationships mean that more than one distinct

Answer 1

As Pablo suggests, interface approach is almost always the right thing to do to handle this. To really utilize switch, another alternative is to have a custom enum denoting your type in your classes.

enum ObjectType { A, B, Default }

interface IIdentifiable
{
    ObjectType Type { get; };
}
class A : IIdentifiable
{
    public ObjectType Type { get { return ObjectType.A; } }
}

class B : IIdentifiable
{
    public ObjectType Type { get { return ObjectType.B; } }
}

void Foo(IIdentifiable o)
{
    switch (o.Type)
    {
        case ObjectType.A:
        case ObjectType.B:
        //......
    }
}

This is kind of implemented in BCL too. One example is MemberInfo.MemberTypes, another is GetTypeCode for primitive types, like:

void Foo(object o)
{
    switch (Type.GetTypeCode(o.GetType())) // for IConvertible, just o.GetTypeCode()
    {
        case TypeCode.Int16:
        case TypeCode.Int32:
        //etc ......
    }
}