Using Fully Qualified Names

Namespaces and types have unique names, which are described by fully qualified names that indicate a logical hierarchy. For example, A.B is the name of the namespace or type B nested in the namespace or type A.

In the following code segment, there are nested classes and namespaces. The fully qualified name is indicated as a comment following each entity.

namespace N1     // N1
{
   class C1      // N1.C1
   {
      class C2   // N1.C1.C2
      {
      }
   }
   namespace N2  // N1.N2
   {
      class C2   // N1.N2.C2
      {
      }
   }
}

In the preceding code segment:

• The namespace N1 is a member of the global namespace. Its fully qualified name is N1.
• The namespace N2 is a member of N1. Its fully qualified name is N1.N2.
• The class C1 is a member of the N1. Its fully qualified name is N1.C1.
• The class name C2 is used twice in this code. However, the fully qualified names are unique. The first one is declared inside C1; thus its fully qualified name is: N1.C1.C2. The second is declared inside a namespace N2; thus, its fully qualified name is N1.N2.C2.

Using the preceding code segment, you can add a new class member C3 to the namespace N1.N2 as follows:

namespace N1.N2 
{
   class C3   // N1.N2.C3
   {
   }
}

For more information on namespaces, see Namespaces.

See Also

C# Language Tour