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Option Strict Off Imports System Imports System.IO Imports System.Runtime.Serialization Imports System.Runtime.Serialization.Formatters.Binary Public Module SerializationSample 'Class Node to hold the Linklist Item. Must be marked as 'serializable <Serializable()> Public Class Node Public Value As Integer Public NextNode As Node = Nothing 'Constructor Public Sub New(ByVal NewValue As Integer) MyBase.New() Me.Value = NewValue End Sub End Class 'Linked List Class. MUst be marked with 'serializable attribute <Serializable()> Public Class LinkedList Private m_head As Node = Nothing Private m_tail As Node = Nothing 'Adding to Linklist Public Function Add(ByVal iValue As Integer) As Boolean Dim curNode As Node = m_head While Not (curNode Is Nothing) If (curNode.Value = iValue) Then Return False curNode = curNode.NextNode End While Dim newNode As Node = New Node(iValue) If (m_tail Is Nothing) Then m_tail = newNode m_head = m_tail Else m_tail.NextNode = newNode m_tail = newNode End If Return True End Function 'Remove from link list Public Function Remove(ByVal iValue As Integer) _ As Boolean Dim prevNode As Node = Nothing Dim curNode As Node = m_head While Not (curNode Is Nothing) If (curNode.Value = iValue) Then If (prevNode Is Nothing) Then If (m_head Is m_tail) Then m_tail = Nothing m_head = m_tail Else m_head = m_head.NextNode End If Else prevNode.NextNode = curNode.NextNode Exit While End If Return True End If prevNode = curNode curNode = curNode.NextNode End While Return False End Function 'Find a specific node in linklist Public Function FindNode(ByVal iValue As Integer) As Node Dim curNode As Node = m_head While Not (curNode Is Nothing) If curNode.Value = iValue Then Return curNode curNode = curNode.NextNode End While Return Nothing End Function 'Swap the Node position in linked list Public Function SwapPositions(ByVal iValue1 As Integer, _ ByVal iValue2 As Integer) As Boolean Dim curNode As Node = m_head Dim Node1 As Node = Nothing Dim Node2 As Node = Nothing Dim prevNode As Node = Nothing Dim prevNode1 As Node = Nothing Dim prevNode2 As Node = Nothing If iValue1 = iValue2 Then Return False End If While Not (curNode Is Nothing) If (curNode.Value = iValue1) Then prevNode1 = prevNode Node1 = curNode ElseIf (curNode.Value = iValue2) Then prevNode2 = prevNode Node2 = curNode End If If (Not (Node1 Is Nothing)) And (Not (Node2 Is Nothing)) Then Exit While End If prevNode = curNode curNode = curNode.NextNode End While If Node1 Is Nothing Or Node2 Is Nothing Then _ Return False If (prevNode1 Is Nothing) Then m_head = Node2 Else prevNode1.NextNode = Node2 End If If (prevNode2 Is Nothing) Then m_head = Node1 Else prevNode2.NextNode = Node1 End If Dim tmp As Node = Node1.NextNode Node1.NextNode = Node2.NextNode Node2.NextNode = tmp Return True End Function 'Display Public Sub Draw() Dim curNode As Node = m_head Debug.Write("List: ") While Not (curNode Is Nothing) Debug.Write(curNode.Value & " ") curNode = curNode.NextNode End While Debug.WriteLine("") End Sub End Class 'Serialization implementation. Public Class Ser ReadOnly iMinValue As Integer = 1 ReadOnly iMaxValue As Integer = 9 Public Sub Scope1() Dim list As LinkedList = New LinkedList() Dim i As Integer Debug.WriteLine("Entering Scope 1") Debug.WriteLine("Creating and filling List ..") For i = iMinValue To iMaxValue - 1 list.Add(i) Next SaveListToDisk(list) Debug.WriteLine("Leaving Scope 1\n") End Sub Public Sub Scope2() Debug.WriteLine("Entering Scope 2") Dim list As LinkedList = LoadListFromDisk() Debug.WriteLine("Swapping Entries") Debug.WriteLine("Swapping 1 and 2") list.SwapPositions(1, 2) Debug.WriteLine("Swapping 3 and 4") list.SwapPositions(3, 4) Debug.WriteLine("Swapping 5 and 6") list.SwapPositions(5, 6) Debug.WriteLine("Swapping 7 and 8") list.SwapPositions(7, 8) SaveListToDisk(list) Debug.WriteLine("Leaving Scope 2\n") End Sub Public Sub Scope3() Debug.WriteLine("Entering Scope 3") Dim list As LinkedList = LoadListFromDisk() Debug.WriteLine("Swapping Random Entries") Dim rnd As Random = New Random() Dim num1, num2, i As Integer For i = 0 To 15 While (True) num1 = rnd.Next(iMinValue, iMaxValue + 1) num2 = rnd.Next(iMinValue, iMaxValue + 1) If num1 <> num2 Then Exit While End If End While Debug.WriteLine("Swapping " & num1 _ & " and " & num2) list.SwapPositions(num1, num2) Next SaveListToDisk(list) Debug.WriteLine("Leaving Scope 3\n") End Sub Public Sub Scope4() Debug.WriteLine("Entering Scope 4") Dim list As LinkedList = LoadListFromDisk() Debug.WriteLine("Removing Entries") Debug.WriteLine("Removing 1") list.Remove(1) Debug.WriteLine("Removing 2") list.Remove(2) Debug.WriteLine("Removing 3") list.Remove(3) SaveListToDisk(list) Debug.WriteLine("Leaving Scope 4\n") End Sub Private Function LoadListFromDisk() As LinkedList Debug.WriteLine _ ("Deserializing LinkedList from file ..") Dim s As Stream = New FileStream("linkedlist.bin", FileMode.Open) Dim b As BinaryFormatter = New BinaryFormatter() 'This casting requires option strict option of vb to ' be off 'While compliing the code use the ' switch /optionstrict- Dim list As LinkedList = b.Deserialize(s) s.Close() list.Draw() Return list End Function Private Sub SaveListToDisk(ByRef list As LinkedList) list.Draw() Debug.WriteLine _ ("Serializing LinkedList to file ..") Dim s As Stream = New FileStream("linkedlist.bin", FileMode.Create) Dim b As BinaryFormatter = New BinaryFormatter() b.Serialize(s, list) s.Close() End Sub End Class Sub Main() Dim SerSample As Ser = New Ser() With SerSample .Scope1() .Scope2() .Scope3() .Scope4() End With End Sub End Module