Stack Class

Category:

Lists, Collections and Arrays

Type:

Classes

Difficulty:

Intermediate

Author:

anton oey

Version Compatibility: Visual Basic 6

More information:

A stack object implemented as an active x .dll, with methods such as AddToBottom, AddToTop, AllItems (returns items in stack as an array), FindItem, PopTopItem, PopBottomItem, and more.

Instructions: Copy the declarations and code below and paste directly into your VB project.

Declarations:
' (None)

Code:

'################################################################
'#  STACK OPERATIONS
'#  Author : Anton Oey
'#  Date   : November 15th, 2001
'#  Usage  :
'#           dim data
'#           dim s as object
'#           set s = new stack
'#
'#           s.AddBottomStack("anton") //to insert item from back
'#           data = s.AllItem   //to get all stack items in array
'#           ... see public function or sub ... etc
'#           set s = nothing
'#
'####################################################################
    
    Private Const LINEARSEARCH As Integer = 1
    Private Const DEFAULTSIZE As Integer = 1000
    
    Private Stack()
    Private arraystack()
    Private UserArray()
    Private UserObject()
    Private arraycounter As Integer
    Private counter As Integer
    Private myItemCounter As Integer
    Private MAXIMUMITEM As Integer
    Private SEARCH As Integer
    
    Public Property Let StackSize(item)
        MAXIMUMITEM = item
    End Property
    
    Public Property Let SearchMethod(item)
        SEARCH = CInt(item)
    End Property
    
    Public Sub SetDefault()
        MAXIMUMITEM = 0
        SEARCH = 1
    End Sub
    
    Public Function AddBottomStack(item) As Boolean
        If MAXIMUMITEM = 0 Then
            MAXIMUMITEM = DEFAULTSIZE
        End If
        If MAXIMUMITEM > (counter - 1) Then
            If item <> "" Then
                ReDim Preserve Stack(counter)
                Stack(counter) = CStr(Trim(item))
                counter = counter + 1
                AddBottomStack = True
            Else
                AddBottomStack = False
            End If
        Else
            AddBottomStack = False
        End If
    End Function
    
    Public Function AddFrontStack(item) As Boolean
        Dim n As Integer
        If MAXIMUMITEM = 0 Then
            MAXIMUMITEM = DEFAULTSIZE
        End If
        If MAXIMUMITEM > (counter - 1) Then
            If item <> "" Then
                ReDim Preserve Stack(counter)
                n = UBound(Stack)
                Do While True
                    If n = 0 Then
                        Exit Do
                    End If
                    Stack(n) = Stack(n - 1)
                    n = n - 1
                Loop
                Stack(LBound(Stack)) = CStr(Trim(item))
                counter = counter + 1
                AddFrontStack = True
            Else
                AddFrontStack = False
            End If
        Else
            AddFrontStack = False
        End If
    End Function
    
    Public Function RemoveItem(item) As Boolean
        If FindItem(item) <> -1 Then
            For n = LBound(Stack) To UBound(Stack)
                If CStr(Trim(item)) <> CStr(Stack(n)) Then
                    ReDim Preserve arraystack(arraycounter)
                    arraystack(arraycounter) = Stack(n)
                    arraycounter = arraycounter + 1
                End If
            Next
            arraycounter = 0
            counter = 0
            ReDim Stack(counter)
            For n = LBound(arraystack) To UBound(arraystack)
                AddBottomStack (arraystack(n))
            Next
            ReDim arraystack(arraycounter)
            RemoveItem = True
        Else
            RemoveItem = False
        End If
    End Function
    
    Private Function IsArrayEmpty(checkArray) As Boolean
            MsgBox (LBound(Stack) & " " & UBound(Stack))
            If LBound(checkArray) = UBound(checkArray) Then
                If checkArray(LBound(checkArray)) = "" Then
                    IsArrayEmtpy = True
                Else
                    IsArrayEmtpy = False
                End If
            Else
                IsArrayEmtpy = False
            End If
    End Function
    
    Public Function IsStackEmpty() As Boolean
            If LBound(Stack) = UBound(Stack) Then
                If Sta...

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Download stack.zip