In C#, why can't a List object be stored in a List<object> variable

Question

It seems that a List object cannot be stored in a List variable in C#, and can\'t even be explicitly cast that way.

List sl = new List

        

Answer 1

If you're using .NET 3.5 have a look at the Enumerable.Cast method. It's an extension method so you can call it directly on the List.

List<string> sl = new List<string>();
IEnumerable<object> ol;
ol = sl.Cast<object>();

It's not exactly what you asked for but should do the trick.

Edit: As noted by Zooba, you can then call ol.ToList() to get a List

Answer 2

Yes, you can, from .NET 3.5:

List<string> sl = new List<string>();
List<object> ol = sl.Cast<object>().ToList();