Imports System
Imports System.Collections.Generic
Class Example
    Public Shared Sub Main()
        Try

            Dim boxEqC As New BoxEqualityComparer()

            Dim boxes As Dictionary(Of Box, [String]) = _
                        New Dictionary(Of Box, String)(boxEqC)

            Dim redBox As New Box(4, 3, 4)
            Dim blueBox As New Box(4, 3, 4)

            boxes.Add(redBox, "red")
            boxes.Add(blueBox, "blue")

        Catch argEx As ArgumentException
            Console.WriteLine(argEx.Message)
        End Try
    End Sub
End Class

Public Class Box
    Public Sub New(ByVal h As Integer, ByVal l As Integer, _
                                        ByVal w As Integer)
        Me.Height = h
        Me.Length = l
        Me.Width = w
    End Sub
    Private _Height As Integer
    Public Property Height() As Integer
        Get
            Return _Height
        End Get
        Set(ByVal value As Integer)
            _Height = value
        End Set
    End Property
    Private _Length As Integer
    Public Property Length() As Integer
        Get
            Return _Length
        End Get
        Set(ByVal value As Integer)
            _Length = value
        End Set
    End Property
    Private _Width As Integer
    Public Property Width() As Integer
        Get
            Return _Width
        End Get
        Set(ByVal value As Integer)
            _Width = value
        End Set
    End Property
End Class


Class BoxEqualityComparer
    Implements IEqualityComparer(Of Box)

    Public Overloads Function Equals(ByVal b1 As Box, ByVal b2 As Box) _
                   As Boolean Implements IEqualityComparer(Of Box).Equals

        If b1.Height = b2.Height And b1.Length = _
                b2.Length And b1.Width = b2.Width Then
            Return True
        Else
            Return False
        End If
    End Function


    Public Overloads Function GetHashCode(ByVal bx As Box) _
                As Integer Implements IEqualityComparer(Of Box).GetHashCode
        Dim hCode As Integer = bx.Height Xor bx.Length Xor bx.Width
        Return hCode.GetHashCode()
    End Function

End Class