Scope-resolution operator :: versus member-access operator . in C#

Question

In C#, what\'s the difference between A::B and A.B? The only difference I\'ve noticed is that only :: can be used with global

Answer 1

with :: you can do things like...

 extern alias X;
 extern alias Y;
 class Test
 {
   X::N.A a;
   X::N.B b1;
   Y::N.B b2;
   Y::N.C c;
 }

and there are times when . is ambiguous so :: is needed. here's the example from the C# language spec

namespace N
{
   public class A {}
   public class B {}
}
namespace N
{
   using A = System.IO;
   class X
   {
      A.Stream s1;         // Error, A is ambiguous
      A::Stream s2;        // Ok
   }
}

http://download.microsoft.com/download/0/B/D/0BDA894F-2CCD-4C2C-B5A7-4EB1171962E5/CSharp%20Language%20Specification.htm