How to get instance of extended object at runtime

[TnTinMN]

Would using reflection acceptable?

I think dee-u has the right idea, just not the implementation.

public void AddAccount(AccountBase account)
{
    Type accountType = account.GetType();
    // assumes DoSomeThing is static if not mi will need to be changed appropriately and change the invoke to use an instance
    MethodInfo mi = typeof(ThirdParty).GetMethod("DoSomeThing", BindingFlags.Static | BindingFlags.Public);

    MethodInfo genMI = mi.MakeGenericMethod(accountType);

    genMI.Invoke(null, new object[] { account });
}