Cast object to unknown type

I would like to create a dynamic method that populates a dropdownlist with any object based on the parameters. Here's my code:

PopulateDropDownList(ddl, GetList(), typeof(MyClass));

public void PopulateDropDownList(DropDownList ddl, IEnumerable list, Type type)
{
    object obj = Activator.CreateInstance(type);
    foreach (var item in list)
        ddl.Items.Add(new ListItem(((obj)item).Name, ((obj)item).ID.ToString()));
}

Basically, what I want to do is to cast Name and ID to a type but I'm getting an error when I compile.