VB简单堆栈类的实现

Private Stack() As String
Private itemCount As Long
Private Sub Class_Initialize()
    ReDim Stack(0)
End Sub
Public Sub Push(ByVal inString As String)
    ReDim Preserve Stack(itemCount + 1)
    Stack(itemCount + 1) = inString
    itemCount = itemCount + 1
End Sub

Public Function Pop() As String
    If itemCount >= 1 Then
        Pop = Stack(itemCount)
        ReDim Preserve Stack(itemCount - 1)
        itemCount = itemCount - 1
    Else
        Pop = ""
    End If
End Function
Public Function Peek() As String
    Peek = Stack(itemCount)
End Function

Sub Clear()
    itemCount = 0
    ReDim Stack(itemCount)
End Sub

Public Function Count()
    Count = itemCount
End Function