visual basic 2010 broncode voorbeelden

Namespace IComparerExample
    Class SomeKey : Implements IComparable
        Public Value1 As Integer
        Public Value2 As Integer
        Public Function CompareTo(ByVal obj As Object) As Integer _
                                         Implements System.IComparable.CompareTo
            If obj Is Nothing Then
                CompareTo = 1
            ElseIf Not TypeOf obj Is SomeKey Then
                Throw New ArgumentException("An invalid argument was " & _
                         "specified.  An argument of type SomeKey is required.")
            Else
                CompareTo = Me.Value1.CompareTo(DirectCast(obj, SomeKey).Value1)
            End If
        End Function
    End Class
    Class SomeKeyComparer : Implements IComparer
        Public Function Compare(ByVal x As Object, ByVal y As Object) _
                      As Integer Implements System.Collections.IComparer.Compare
            If x IsNot Nothing AndAlso y Is Nothing Then
                Return 1
            ElseIf x Is Nothing AndAlso y IsNot Nothing Then
                Return -1
            ElseIf x IsNot Nothing AndAlso y IsNot Nothing Then
                If TypeOf x Is SomeKey AndAlso TypeOf y Is SomeKey Then
                    Compare = DirectCast(x, SomeKey).Value2. _
                                        CompareTo(DirectCast(y, SomeKey).Value2)
                Else
                    Throw New ArgumentException("x and y are of different " & _
                 "types and neither one can handle comparisons with the other.")
                End If
            End If
        End Function
    End Class
    Class Client
        Public Shared Sub Main()
            Dim key1 As New SomeKey With {.Value1 = 1, .Value2 = 3}
            Dim key2 As New SomeKey With {.Value1 = 2, .Value2 = 2}
            Dim key3 As New SomeKey With {.Value1 = 3, .Value2 = 1}
            '
            Dim comparer1 As IComparer = New SomeKeyComparer
            '
            Dim sortedList1 As New SortedList()
            Dim sortedList2 As New SortedList(comparer1)
            '
            sortedList1.Add(key1, "value1")
            sortedList1.Add(key2, "value2")
            sortedList1.Add(key3, "value3")
            '
            sortedList2.Add(key1, "value4")
            sortedList2.Add(key2, "value5")
            sortedList2.Add(key3, "value6")
            '
            For Each entry As DictionaryEntry In sortedList1
                Console.WriteLine(entry.Value)
            Next
            Console.WriteLine()
            '
            For Each entry As DictionaryEntry In sortedList2
                Console.WriteLine(entry.Value)
            Next
            '
            Console.ReadLine()
        End Sub
    End Class
End Namespace

value1
value2
value3

value6
value5
value4