' Visual Basic 2008 9.0 .NET Examples - Parameter Arrays - ParamArray - Procedures and Functions : 
Module Example1
    Sub Main()
        Console.WriteLine(GetSum(1, 2, 3, 4, 5))
        Console.WriteLine(GetSum(1, 2, 3, 4))
        Console.WriteLine(GetSum(1, 2, 3))
        Console.WriteLine(GetSum(1, 2))
        Console.WriteLine(GetSum(1))
        Console.WriteLine(GetSum())                                        ' (1)
        '
        Console.ReadLine()
    End Sub
    Function GetSum(ByVal ParamArray values As Integer()) As Integer
        If values IsNot Nothing Then
            For Each value As Integer In values
                GetSum += value
            Next
        End If
    End Function
End Module
Module Example2
    Sub Main()
        Dim values As Integer() = {1, 2, 3, 4, 5}
        Console.WriteLine(Example1.GetSum(values))
        '
        values = Nothing
        Console.WriteLine(Example1.GetSum(values))                        ' (1)
        '
        Console.ReadLine()
    End Sub
End Module
Module Exercise1Task
    Sub Main()
        Console.WriteLine(Exercise1Solution.GetConcatenation("abc", "def", _
                                                             "ghi"))
        Console.WriteLine(Exercise1Solution.GetConcatenation("abc", "def"))
        Console.WriteLine(Exercise1Solution.GetConcatenation("abc"))
        Console.WriteLine(Exercise1Solution.GetConcatenation())
        '
        Dim words As String() = {"abc", "def", "ghi"}
        Console.WriteLine(Exercise1Solution.GetConcatenation(words))
        '
        words = Nothing
        Console.WriteLine(Exercise1Solution.GetConcatenation(words))
        '
        Console.ReadLine()
    End Sub
End Module
Module Exercise1Solution
    Function GetConcatenation(ByVal ParamArray words As String()) As String
        If words IsNot Nothing Then
            For Each word As String In words
                GetConcatenation &= word
            Next
        End If
    End Function
End Module
Module Exercise2Task
    Sub Main()
        Dim values As Integer() = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
        Example1.PrintArray(values)
        '
        Dim count As Integer = 5
        Dim valuesCopy As Integer()
        valuesCopy = Exercise2Solution.GetIntegerArrayCopy(values, count)
        Example1.PrintArray(valuesCopy)
        '
        Dim factor As Integer = 4
        count = 3
        Exercise2Solution.MultiplyIntegerValues(valuesCopy, count, factor)
        '
        Example1.PrintArray(values)
        Example1.PrintArray(valuesCopy)
        '
        count = 6
        Exercise2Solution.MultiplyIntegerValues(values, count)
        '
        Example1.PrintArray(values)
        Example1.PrintArray(valuesCopy)
        '
        Console.ReadLine()
    End Sub
End Module
Module Exercise2Solution
    Function GetIntegerArrayCopy(ByVal values As Integer(), _
                                 ByVal count As Integer) As Integer()
        Dim valuesCopy(count - 1) As Integer
        For index As Integer = 0 To count - 1
            valuesCopy(index) = values(index)
        Next
        GetIntegerArrayCopy = valuesCopy
    End Function
    Sub MultiplyIntegerValues(ByVal values As Integer(), _
                              ByVal count As Integer, _
                              Optional ByVal factor As Integer = 2)
        For index As Integer = 0 To count - 1
            values(index) *= factor
        Next
    End Sub
End Module

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