Does every type in .net inherit from System.Object? [duplicate]

Question

This might be a very basic question, but I am a bit confused about it. If I reflect the Int32/Double/any value type code, I see that they are structs and look like :

[Serializable, StructLayout(LayoutKind.Sequential), ComVisible(true)] public struct Double : IComparable, IFormattable, IConvertible, IComparable<double>, IEquatable<double> { .... } 

So, why do we say that everything in .NET is derived from System.Object. I think am missing some crucial point here.

EDIT: What confuses me further is that how can a value type which is struct inherit from System.Object which is a class.

Answer 1

Eric Lippert has covered this in a blog entry: Not everything derives from object (This is the title of the blog entry; not the answer to this question. Don't get confused.)

Yes, all structs inherit from System.ValueType which in turn inherits from System.Object. enums you declare inherit from System.Enum which inherits from System.ValueType.

Update:

Inherently, there's not a problem with a value type being derived from a reference type. Inheritance is a "is-a" relationship between two types. However, in order to treat a value type as an object instance, it has to be boxed. This is done implicitly when you are passing a value to a method that expects an object parameter (or when you call instance methods implemented in System.Object.)