Imports System
Imports System.Collections
Imports System.Diagnostics
Imports System.Reflection



Class DebugViewTest

    Shared Sub Main(ByVal args() As String) 
        Dim myHashTable As New MyHashtable()
        myHashTable.Add("one", 1)
        myHashTable.Add("two", 2)
        Console.WriteLine(myHashTable.ToString())
        Console.WriteLine("In Main.")

    End Sub 'Main 
End Class 'DebugViewTest
<DebuggerDisplay("{value}", Name := "{key}")>  _
Friend Class KeyValuePairs
    Private dictionary As IDictionary
    Private key As Object
    Private value As Object


    Public Sub New(ByVal dictionary As IDictionary, ByVal key As Object, ByVal value As Object) 
        Me.value = value
        Me.key = key
        Me.dictionary = dictionary

    End Sub 'New
End Class 'KeyValuePairs
<DebuggerDisplay("Count = {Count}"), DebuggerTypeProxy(GetType(MyHashtable.HashtableDebugView))> _
Class MyHashtable
    Inherits Hashtable
    Private Const TestString As String = "This should not appear in the debug window."


    Friend Class HashtableDebugView
        Private hashtable As Hashtable
        Public Const TestString As String = "This should appear in the debug window."

        Public Sub New(ByVal hashtable As Hashtable)
            Me.hashtable = hashtable

        End Sub 'New
    End Class 'HashtableDebugView 
End Class 'MyHashtable

using System;
using System.Collections;
using System.Diagnostics;
using System.Reflection;

class DebugViewTest
{
    // The following constant will appear in the debug window for DebugViewTest.
    const string TabString = "    ";
    // The following DebuggerBrowsableAttribute prevents the property following it 
    // from appearing in the debug window for the class.
    [DebuggerBrowsable(DebuggerBrowsableState.Never)]
    public static string y = "Test String";

    static void Main(string[] args)
    {
        MyHashtable myHashTable = new MyHashtable();
        myHashTable.Add("one", 1);
        myHashTable.Add("two", 2);
        Console.WriteLine(myHashTable.ToString());
        Console.WriteLine("In Main.");

 }
}
[DebuggerDisplay("{value}", Name = "{key}")]
internal class KeyValuePairs
{
    private IDictionary dictionary;
    private object key;
    private object value;

    public KeyValuePairs(IDictionary dictionary, object key, object value)
    {
        this.value = value;
        this.key = key;
        this.dictionary = dictionary;
    }
}
[DebuggerDisplay("Count = {Count}")]
[DebuggerTypeProxy(typeof(HashtableDebugView))]
class MyHashtable : Hashtable
{
    private const string TestString = "This should not appear in the debug window.";

    internal class HashtableDebugView
   {
      private Hashtable hashtable;
      public const string TestString = "This should appear in the debug window.";
      public HashtableDebugView(Hashtable hashtable)
      {
         this.hashtable = hashtable;
      }

      [DebuggerBrowsable(DebuggerBrowsableState.RootHidden)]
      public KeyValuePairs[] Keys
      {
         get 
         {
             KeyValuePairs[] keys = new KeyValuePairs[hashtable.Count];

            int i = 0;
            foreach(object key in hashtable.Keys)
            {
               keys[i] = new KeyValuePairs(hashtable, key, hashtable[key]);
               i++;
            }
         return keys;
         }
      }
   }
}