visual basic 2010 broncode voorbeelden

Public Enum File
    FileA
    FileB
    ' ...
End Enum
Public Enum Rank
    Rank1
    Rank2
    ' ...
End Enum
Public Class Square
    Public Sub New(ByVal file As File, ByVal rank As Rank)
        _File = file
        _Rank = rank
    End Sub
    Private ReadOnly _File As File
    Public ReadOnly Property File() As File
        Get
            File = _File
        End Get
    End Property
    Private ReadOnly _Rank As Rank
    Public ReadOnly Property Rank() As Rank
        Get
            Rank = _Rank
        End Get
    End Property
End Class
Class SquareComparer : Implements IEqualityComparer
    Public Function Equals(ByVal x As Object, ByVal y As Object) As Boolean _
                                             Implements IEqualityComparer.Equals
        If x IsNot Nothing AndAlso y IsNot Nothing AndAlso _
           TypeOf x Is Square AndAlso TypeOf y Is Square Then
            Dim squareX As Square = DirectCast(x, Square)
            Dim squareY As Square = DirectCast(y, Square)
            Equals = (x.Rank = y.Rank AndAlso x.File = y.File)
        End If
    End Function
    Public Function GetHashCode(ByVal obj As Object) As Integer _
                                        Implements IEqualityComparer.GetHashCode
        If obj IsNot Nothing AndAlso TypeOf obj Is Square Then
            Dim square As Square = DirectCast(obj, Square)
            GetHashCode = square.File Xor square.Rank
        End If
    End Function
End Class
Class Client
    Public Shared Sub Main()
        Dim square1 As New Example1.Square(File.FileA, Rank.Rank1)
        Dim square2 As New Example1.Square(File.FileB, Rank.Rank1)
        Dim square3 As New Example1.Square(File.FileA, Rank.Rank1)
        '
        Dim board As New Hashtable(New SquareComparer)
        board.Add(square1, "R")
        board.Add(square2, "K")
        '
        Console.WriteLine(board.Item(square1).ToString()) ' R
        Console.WriteLine(board.Item(square2).ToString()) ' K
        Console.WriteLine(board.Item(square3).ToString()) ' R
        '
        Console.ReadLine()
    End Sub
End Class

R
K
R