Delegate委托的VB.Net实例

Module Module1

    Delegate Function CompareFunc(ByVal X As Integer, ByVal Y As Integer) As Boolean 'Delegate委托

    Function IsSmaller(ByVal X As Integer, ByVal Y As Integer) As Boolean
        Return X < Y
    End Function

    Function IsBigger(ByVal X As Integer, ByVal Y As Integer) As Boolean
        Return X > Y
    End Function

    Sub MySort(ByVal obj() As Integer, ByVal CompareMethod As CompareFunc)
        Dim I, J, Tmp As Integer
        For I = 0 To obj.Length - 2
            For J = I + 1 To obj.Length - 1
                If CompareMethod.Invoke(obj(J), obj(I)) Then
                    Tmp = obj(J)
                    obj(J) = obj(I)
                    obj(I) = Tmp
                End If
            Next
        Next
    End Sub

    Sub Show(ByVal obj() As Integer)
        Dim I As Integer
        For I = 0 To obj.Length - 1
            Console.Write("{0},", obj(I))
        Next
        Console.WriteLine()
    End Sub

    Sub Main()
        Dim IntArray() As Integer = {34, 21, 54, 32, 12}
        Dim CompareIt As CompareFunc

        Console.Write("乐博网提示：由小排到大:")
        CompareIt = AddressOf IsSmaller
        MySort(IntArray, CompareIt)
        Show(IntArray)

        Console.Write("乐博网提示：由大排到小:")
        MySort(IntArray, AddressOf IsBigger)
        Show(IntArray)

        Console.Read()
    End Sub

End Module