VB.Net Tutorial/Generics/Generic Stack

Generic Stack

<source lang="vbnet">Module StackTest

  Dim doubleElements() As Double = {1.1, 2.2, 3.3, 4.4, 5.5, 6.6}
  Dim integerElements() As Integer = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11}
  Dim doubleStack As Stack(Of Double)
  Dim integerStack As Stack(Of Integer)
  Sub Main()
     doubleStack = New Stack(Of Double)(5)
     integerStack = New Stack(Of Integer)(10)
     TestPushDouble()
     TestPopDouble() 
     TestPushInteger()
     TestPopInteger() 
  End Sub 
  Sub TestPushDouble()
     Try
        Console.WriteLine("Pushing elements onto doubleStack")
        For Each element As Double In doubleElements
           Console.Write("{0:F1} ", element)
           doubleStack.Push(element)
        Next element
     Catch exception As GenericStackException
        Console.Error.WriteLine("Message: " & exception.Message)
        Console.Error.WriteLine(exception.StackTrace)
     End Try
  End Sub
  Sub TestPopDouble()
     Try
        Console.WriteLine("Popping elements from doubleStack")
        Dim popValue As Double
        While True
           popValue = doubleStack.Pop()
           Console.Write("{0:F1} ", popValue)
        End While
     Catch exception As GenericStackException
        Console.Error.WriteLine()
        Console.Error.WriteLine("Message: " & exception.Message)
        Console.Error.WriteLine(exception.StackTrace)
     End Try
  End Sub
  Sub TestPushInteger()
     Try
        Console.WriteLine("Pushing elements onto integerStack")
        For Each element As Integer In integerElements
           Console.Write("{0} ", element)
           integerStack.Push(element) " push onto integerStack
        Next element
     Catch exception As GenericStackException
        Console.Error.WriteLine()
        Console.Error.WriteLine("Message: " & exception.Message)
        Console.Error.WriteLine(exception.StackTrace)
     End Try
  End Sub
  
  Sub TestPopInteger()
     Try
        Console.WriteLine("Popping elements from integerStack")
        Dim popValue As Integer
        While True
           popValue = integerStack.Pop()
           Console.Write("{0} ", popValue)
        End While
     Catch exception As GenericStackException
        Console.Error.WriteLine()
        Console.Error.WriteLine("Message: " & exception.Message)
        Console.Error.WriteLine(exception.StackTrace)
     End Try
  End Sub

End Module Public Class Stack(Of E)

  Private top As Integer
  Private elements() As E
  Public Sub New()
     MyClass.New(10)
  End Sub " New
  Public Sub New(ByVal stackSize As Integer)
     If stackSize > 0 Then 
        elements = New E(stackSize - 1) {}
     Else
        elements = New E(9) {}
     End If
     top = -1
  End Sub " New
  Public Sub Push(ByVal pushValue As E)
     If top = elements.Length - 1 Then
        Throw New GenericStackException(String.Format("Stack is full, cannot push {0}", pushValue))
     End If
     top += 1
     elements(top) = pushValue 
  End Sub
  Public Function Pop() As E
     If top = -1 Then
        Throw New GenericStackException("Stack is empty, cannot pop")
     End If
     top -= 1
     Return elements(top + 1) 
  End Function 

End Class

Public Class GenericStackException : Inherits ApplicationException

  Public Sub New()
     MyBase.New("Stack is empty")
  End Sub " New
  Public Sub New(ByVal exception As String)
     MyBase.New(exception)
  End Sub

End Class</source>

Pushing elements onto doubleStack
1.1 2.2 3.3 4.4 5.5 6.6 Message: Stack is full, cannot push 6.6
   at Stack`1.Push(E pushValue)
   at StackTest.TestPushDouble()
Popping elements from doubleStack
5.5 4.4 3.3 2.2 1.1
Message: Stack is empty, cannot pop
   at Stack`1.Pop()
   at StackTest.TestPopDouble()
Pushing elements onto integerStack
1 2 3 4 5 6 7 8 9 10 11
Message: Stack is full, cannot push 11
   at Stack`1.Push(E pushValue)
   at StackTest.TestPushInteger()
Popping elements from integerStack
10 9 8 7 6 5 4 3 2 1
Message: Stack is empty, cannot pop
   at Stack`1.Pop()
   at StackTest.TestPopInteger()