how to get type of nested class with Type.GetType(string)

Question

I can create a new class with a fully qualified name like Namespace.OuterClass.NestedClass. But attempting to get the type with Type.GetType("Namespace.OuterClass.NestedClass") returns null. Here is sample code:

namespace Sample
{
   public class Program
   {
      public class Animal { }
      public class Vegetable { }
      public class Mineral { }

      static public void Test()
      {
         Object o = new Sample.Program.Vegetable();
         Type t = Type.GetType("Sample.Program.Vegetable"); // returns null
         Console.ReadKey();
      }

      static void Main(string[] args)
      {
         Program.Test();
      }
   }
}

How can I use Type.GetType for a nested class?

Answer 1

String values for C# fully qualified names use + between classes. Get the type by string with Type.GetType("Namespace.OuterClass+NestedClass").

MSDN documentation for Type.GetType(string) gives a syntax table for various types (generic types, arguments, unmanaged pointers, etc.) including "parent class and a nested class".

Adding these lines to the question's sample code:

string typeName1 = typeof(Sample.Program.Vegetable).FullName;
string typeName2 = typeof(Vegetable).FullName;

will prove the string type name equal to Sample.Program+Vegetable

ECMA-335 Partition IV's associated CLILibrary.xml provides the definitive details for this convention. The Type.GetType(string) syntax table in ECMA-335 is identical to that used in the MSDN documentation.