一个简单的树类

树类#Region "树类"

树型项目类#Region "树型项目类"
Public Class CTreeItemClass CTreeItem

  Private intParentDataID As Integer = -1
  Private intLevel As Integer = -1

  Public DataID As Integer
  Public Name As String
  Public Value As String
  Public OtherInfo As COtherInfo

  Public Items As CTreeItemCollection

  Private _ParentTree As CTree
  Public Property ParentTree()Property ParentTree() As CTree
    Get
      Return _ParentTree
    End Get
    Set(ByVal Value As CTree)
      _ParentTree = Value
    End Set
  End Property

  Private _ParentTreeItem As CTreeItem
  Public Property ParentTreeItem()Property ParentTreeItem() As CTreeItem
    Get
      Return _ParentTreeItem
    End Get
    Set(ByVal Value As CTreeItem)
      _ParentTreeItem = Value
    End Set
  End Property

  Public Sub New()Sub New()
    Me.Items = New CTreeItemCollection(Me)
    Me.OtherInfo = New COtherInfo
  End Sub

  Public ReadOnly Property ParentDataID()Property ParentDataID() As Integer
    Get
      If intParentDataID = -1 Then
        If Not _ParentTreeItem Is Nothing Then
intParentDataID = _ParentTreeItem.DataID
        ElseIf Not _ParentTree Is Nothing Then
          intParentDataID = 0
        End If
      End If
      Return intParentDataID
    End Get
  End Property

  Public ReadOnly Property Level()Property Level() As Integer
    Get
      If (intLevel <> -1) Then
        Return intLevel
      End If
      Dim TI As Object = Me.ParentTreeItem
      Do While TypeOf TI Is CTreeItem
        TI = CType(TI, CTreeItem).ParentTreeItem
        intLevel += 1
      Loop
      intLevel += 1
      Return intLevel
    End Get
  End Property

  Private Function GetPrevOrNextTreeItem()Function GetPrevOrNextTreeItem(ByVal blnGetNext As Boolean) As CTreeItem
    If ((Me.ParentTreeItem Is Nothing) AndAlso (Me.ParentTree Is Nothing)) Then
      Throw New Exception("未设置 ParentTreeItem 或 ParentTree 属性，不能获取上一个或下一个项目。")
    End If

    Dim TIC As CTreeItemCollection
    If Me.ParentTreeItem Is Nothing Then
      TIC = Me.ParentTree.Items
    Else
      TIC = Me.ParentTreeItem.Items
    End If

    Dim num1 As Integer = TIC.IndexOf(Me)

    If blnGetNext Then
      If (num1 >= (TIC.Count - 1)) Then
        Return Nothing
      End If
      Return TIC.Item(num1 + 1)
    Else
      If (num1 <= 0) Then
        Return Nothing
      End If
      Return TIC.Item((num1 - 1))
    End If
  End Function

  Public ReadOnly Property PrevTreeItem()Property PrevTreeItem() As CTreeItem
    Get
      Return GetPrevOrNextTreeItem(False)
    End Get
  End Property

  Public ReadOnly Property NextTreeItem()Property NextTreeItem() As CTreeItem
    Get
      Return GetPrevOrNextTreeItem(True)
    End Get
  End Property

  Private strPath As String
  Public Function Path()Function Path() As String
    If strPath Is Nothing OrElse strPath.Length = 0 Then
      If Not Me._ParentTreeItem Is Nothing Then
        strPath = Me._ParentTreeItem.Path + "/" + Me.Name
      Else
        strPath = Me.Name
      End If
    End If
    Return strPath
  End Function

  Private strDataIDPath As String
  Public Function DataIDPath()Function DataIDPath() As String
    If Me.DataID > 0 Then
      If strDataIDPath Is Nothing OrElse strDataIDPath.Length = 0 Then
        If Not Me._ParentTreeItem Is Nothing Then
          strDataIDPath = Me._ParentTreeItem.DataIDPath + "/" + Me.DataID.ToString
        Else
          strDataIDPath = Me.DataID.ToString
        End If
      End If
      Return strDataIDPath
    End If
  End Function
End Class

#End Region

树型项目集合类#Region "树型项目集合类"
Public Class CTreeItemCollectionClass CTreeItemCollection
  Inherits CollectionBase

  Public ParentTree As CTree
  Public ParentTreeItem As CTreeItem

  Public Sub New()Sub New()
    MyBase.New()
  End Sub

  Public Sub New()Sub New(ByVal Parent As CTree)
    MyBase.New()
    Me.ParentTree = Parent
  End Sub

  Public Sub New()Sub New(ByVal Parent As CTreeItem)
    MyBase.New()
    Me.ParentTreeItem = Parent
  End Sub

  Public Function Add()Function Add(ByVal TreeItem As CTreeItem) As Integer
    TreeItem.ParentTree = Me.ParentTree
    TreeItem.ParentTreeItem = Me.ParentTreeItem
    Return MyBase.List.Add(TreeItem)
  End Function

  Public Function Item()Function Item(ByVal ItemIndex As Integer) As CTreeItem
    Return MyBase.List.Item(ItemIndex)
  End Function

  Public Function IndexOf()Function IndexOf(ByVal Value As CTreeItem) As Integer
    Return MyBase.List.IndexOf(Value)
  End Function

  Public Function FindByName()Function FindByName(ByVal Name As String) As CTreeItem
    For Each TI As CTreeItem In Me.List
      If TI.Name = Name Then Return TI
    Next
  End Function

  Public Function Remove()Function Remove(ByVal Name As String) As Boolean
    For Each Ti As CTreeItem In Me.List
      If Ti.Name = Name Then
        MyBase.List.Remove(Ti)
        Return True
      End If
    Next
    Return False
  End Function

  Public Function GetValue()Function GetValue(ByVal Name As String) As String
    Dim TI As CTreeItem = FindByName(Name)
    If Not TI Is Nothing Then Return TI.Value
  End Function
End Class
#End Region

Public Class CTreeClass CTree

  Public Items As CTreeItemCollection

  Public Sub New()Sub New()
    Me.Items = New CTreeItemCollection(Me)
  End Sub

  Protected Overrides Sub Finalize()Sub Finalize()
    MyBase.Finalize()
  End Sub
End Class
#End Region