TreeView 控件 (VBComCtlTreeView)

VBComCtlTreeView 控件提供了一个增强的树形视图界面，用于显示层次结构数据。与标准的 MSComCtl TreeView 控件相比，它提供了更好的性能和视觉特性。

属性

主要属性

Nodes：树形视图中所有节点的集合
SelectedItem：返回当前选中的节点
PathSeparator：用于分隔节点层级的字符（默认为 ""）
Indentation：设置子节点的缩进量
LineStyle：控制连接线的外观
CheckBoxes：启用/禁用节点的复选框
SingleSel：启用/禁用单选模式
HideSelection：控件失去焦点时是否隐藏选择
LabelEdit：启用/禁用标签编辑
ImageList：关联的图像列表控件
HotTracking：启用/禁用热跟踪

节点关系常量 (TvwNodeRelationshipConstants)

用于 Nodes.Add 和 TvwNode.Move 方法的 Relationship 参数：

TvwNodeRelationshipFirst (0) - 作为第一个兄弟节点
TvwNodeRelationshipLast (1) - 作为最后一个兄弟节点
TvwNodeRelationshipNext (2) - 作为下一个兄弟节点
TvwNodeRelationshipPrevious (3) - 作为前一个兄弟节点
TvwNodeRelationshipChild (4) - 添加为子节点

TvwNode 对象属性

Key：节点的键值
Text：节点的显示文本
Tag：关联的标签数据
Image：节点的图像索引
SelectedImage：选中时的图像索引
Expanded：节点是否展开
Checked：节点复选框是否选中
Children：子节点数量
Index：节点的索引
Parent：父节点（只读）
Root：根节点（只读）
Child：第一个子节点（只读）
Previous：前一个兄弟节点（只读）
Next：后一个兄弟节点（只读）
FirstSibling：第一个兄弟节点（只读）
LastSibling：最后一个兄弟节点（只读）
FullPath：节点的完整路径（只读）

方法

主要方法

HitTest(X As Single, Y As Single) As TvwNode：测试指定坐标处的节点
HitTestInsertMark(X As Single, Y As Single) As TvwNode：测试插入标记处的节点
StartLabelEdit([Node As TvwNode])：开始标签编辑
EndLabelEdit([Cancel As Boolean])：结束标签编辑
ResetForeColors()：重置前景颜色
GetVisibleCount() As Long：返回可见节点的数量

Nodes 集合方法

Add([Relative As TvwNode], [Relationship As TvwNodeRelationshipConstants], [Key As String], [Text As String], [Image], [SelectedImage]) As TvwNode：添加新节点
Clear()：清除所有节点
Remove(Index)：移除指定节点

TvwNode 对象方法

EnsureVisible()：确保节点可见
CreateDragImage()：创建拖拽图像
Move([Relative As TvwNode], [Relationship As TvwNodeRelationshipConstants])：移动节点
SelectedIndex([Index As Integer])：设置选中图像索引

事件

NodeClick(ByVal Node As TvwNode)：点击节点时触发
BeforeExpand(ByVal Node As TvwNode, Cancel As Integer)：节点展开前触发
AfterExpand(ByVal Node As TvwNode)：节点展开后触发
BeforeCollapse(ByVal Node As TvwNode, Cancel As Integer)：节点折叠前触发
AfterCollapse(ByVal Node As TvwNode)：节点折叠后触发
BeforeLabelEdit(Cancel As Integer)：标签编辑开始前触发
AfterLabelEdit(Cancel As Integer)：标签编辑结束后触发
NodeCheck(ByVal Node As TvwNode)：节点复选框状态改变时触发
KeyDown(KeyCode As Integer, Shift As Integer)
KeyUp(KeyCode As Integer, Shift As Integer)
KeyPress(KeyAscii As Integer)
MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
DblClick()：双击事件
OLEDragDrop(Data As DataObject, Effect As Long, Button As Integer, Shift As Integer, X As Single, Y As Single)
OLEDragOver(Data As DataObject, Effect As Long, Button As Integer, Shift As Integer, X As Single, Y As Single, State As Integer)
OLEStartDrag(Data As DataObject, AllowedEffects As Long)
OLESetData(Data As DataObject, DataFormat As Integer)
OLEGiveFeedback(Effect As Long, DefaultCursors As Boolean)
OLECompleteDrag(Effect As Long)
MouseEnter()：鼠标进入控件时触发
MouseLeave()：鼠标离开控件时触发

代码示例

基本用法

Private Sub Form_Load()
    ' 添加根节点
    Dim rootNode As TvwNode
    Set rootNode = TreeView1.Nodes.Add(, , "root", "根节点", 1, 2)

    ' 添加子节点
    TreeView1.Nodes.Add rootNode, TvwNodeRelationshipChild, "child1", "子节点 1", 3, 4
    TreeView1.Nodes.Add rootNode, TvwNodeRelationshipChild, "child2", "子节点 2", 3, 4

    ' 为子节点 1 添加子节点
    TreeView1.Nodes.Add "child1", TvwNodeRelationshipChild, "grandchild1", "孙节点 1", 5, 6

    ' 展开根节点
    rootNode.Expanded = True
End Sub

处理事件

Private Sub TreeView1_NodeClick(ByVal Node As TvwNode)
    Debug.Print "选中的节点：" & Node.Text
    Debug.Print "节点键值：" & Node.Key
    Debug.Print "节点层级：" & Node.FullPath
    Debug.Print "子节点数：" & Node.Children
End Sub

Private Sub TreeView1_BeforeExpand(ByVal Node As TvwNode, Cancel As Integer)
    ' 示例：动态加载子节点
    If Node.Children = 0 And Not Node.Tag = "loaded" Then
        LoadChildNodes Node
        Node.Tag = "loaded"
    End If
End Sub

Private Sub TreeView1_NodeCheck(ByVal Node As TvwNode)
    Debug.Print "节点 " & Node.Text & " 的复选状态: " & Node.Checked
End Sub

动态节点加载

Private Sub LoadChildNodes(ParentNode As TvwNode)
    ' 示例：加载目录结构
    Dim FSO As Object
    Dim Folder As Object
    Dim SubFolder As Object

    Set FSO = CreateObject("Scripting.FileSystemObject")

    On Error Resume Next
    Set Folder = FSO.GetFolder(ParentNode.Tag)

    If Err.Number = 0 Then
        For Each SubFolder In Folder.SubFolders
            Dim newNode As TvwNode
            Set newNode = TreeView1.Nodes.Add(ParentNode, TvwNodeRelationshipChild, _
                SubFolder.Path, SubFolder.Name, 3, 4)
            newNode.Tag = SubFolder.Path

            ' 如果有子文件夹，添加占位节点
            If SubFolder.SubFolders.Count > 0 Then
                TreeView1.Nodes.Add newNode, TvwNodeRelationshipChild, "placeholder_" & _
                    SubFolder.Path, "", 0, 0
            End If
        Next SubFolder
    End If

    On Error GoTo 0
End Sub

查找节点

Private Function FindNodeByKey(ByVal Key As String) As TvwNode
    Dim Node As TvwNode

    For Each Node In TreeView1.Nodes
        If Node.Key = Key Then
            Set FindNodeByKey = Node
            Exit Function
        End If
    Next Node

    Set FindNodeByKey = Nothing
End Function

Private Function FindNodeByText(ByVal Text As String) As TvwNode
    Dim Node As TvwNode

    For Each Node In TreeView1.Nodes
        If StrComp(Node.Text, Text, vbTextCompare) = 0 Then
            Set FindNodeByText = Node
            Exit Function
        End If
    Next Node

    Set FindNodeByText = Nothing
End Function

常见用例

文件系统浏览器

Private Sub CreateFileSystemTree()
    Dim FSO As Object
    Dim Drive As Object

    Set FSO = CreateObject("Scripting.FileSystemObject")
    TreeView1.Nodes.Clear

    For Each Drive In FSO.Drives
        If Drive.IsReady Then
            Dim nodeKey As String
            nodeKey = "Drive_" & Drive.DriveLetter

            Dim newNode As TvwNode
            Set newNode = TreeView1.Nodes.Add(, , nodeKey, _
                Drive.DriveLetter & ":\", 1, 2)
            newNode.Tag = Drive.DriveLetter & ":\"

            ' 添加占位节点
            TreeView1.Nodes.Add newNode, TvwNodeRelationshipChild, _
                "placeholder_" & nodeKey, "", 0, 0
        End If
    Next Drive
End Sub

组织架构图

Private Sub CreateOrgChart()
    Dim ceo As TvwNode
    Set ceo = TreeView1.Nodes.Add(, , "CEO", "首席执行官", 1, 2)

    ' 添加部门主管
    TreeView1.Nodes.Add ceo, TvwNodeRelationshipChild, "CFO", "首席财务官", 3, 4
    TreeView1.Nodes.Add ceo, TvwNodeRelationshipChild, "CTO", "首席技术官", 3, 4
    TreeView1.Nodes.Add ceo, TvwNodeRelationshipChild, "COO", "首席运营官", 3, 4

    ' 添加团队成员
    TreeView1.Nodes.Add "CTO", TvwNodeRelationshipChild, "Dev1", "开发团队负责人", 5, 6
    TreeView1.Nodes.Add "CTO", TvwNodeRelationshipChild, "Dev2", "测试团队负责人", 5, 6

    ' 展开根节点
    ceo.Expanded = True
End Sub

展开和折叠节点

Private Sub ExpandNode(ByRef Node As TvwNode)
    Node.Expanded = True
End Sub

Private Sub CollapseNode(ByRef Node As TvwNode)
    Node.Expanded = False
End Sub

Private Sub ExpandAll()
    Dim Node As TvwNode
    For Each Node In TreeView1.Nodes
        Node.Expanded = True
    Next Node
End Sub

Private Sub CollapseAll()
    Dim Node As TvwNode
    For Each Node In TreeView1.Nodes
        Node.Expanded = False
    Next Node
End Sub

节点操作

Private Sub RenameNode(ByVal Key As String, ByVal NewText As String)
    Dim Node As TvwNode
    Set Node = FindNodeByKey(Key)

    If Not Node Is Nothing Then
        TreeView1.StartLabelEdit Node
        ' 等待用户输入或直接修改
        Node.Text = NewText
    End If
End Sub

Private Sub DeleteNode(ByVal Key As String)
    Dim Node As TvwNode
    Set Node = FindNodeByKey(Key)

    If Not Node Is Nothing Then
        TreeView1.Nodes.Remove Node.Index
    End If
End Sub

最佳实践

内存管理

Private Sub ClearTree()
    TreeView1.Nodes.Clear
    Set TreeView1.ImageList = Nothing
End Sub

性能优化

Private Sub OptimizedNodeAddition()
    TreeView1.Visible = False

    ' 添加大量节点...

    TreeView1.Visible = True
End Sub

错误处理

Private Sub SafeNodeOperation(NodeKey As String)
    On Error Resume Next
    Dim Node As TvwNode
    Set Node = TreeView1.Nodes(NodeKey)

    If Err.Number = 0 Then
        ' 节点存在，执行操作
        Node.EnsureVisible
        Node.Selected = True
    Else
        ' 处理节点未找到的情况
        Debug.Print "未找到节点：" & NodeKey
    End If
    On Error GoTo 0
End Sub

递归删除节点

Private Sub DeleteNodeRecursive(ByRef Node As TvwNode)
    ' 递归删除所有子节点
    While Node.Children > 0
        Dim Child As TvwNode
        Set Child = Node.Child
        DeleteNodeRecursive Child
    Wend

    ' 删除节点本身
    TreeView1.Nodes.Remove Node.Index
End Sub

其他提示

处理大量节点时，建议使用批量添加方式
使用 Tag 属性存储额外的节点信息
定期清理未使用的节点以优化内存使用
适当使用图标列表来增强视觉效果
考虑使用动态加载处理超大数据集
在 Form_Unload 中清理资源
使用 EnsureVisible 确保选中节点可见
实现适当的错误恢复机制

TreeView 控件 (VBComCtlTreeView) ​

属性 ​

主要属性 ​

节点关系常量 (TvwNodeRelationshipConstants) ​

TvwNode 对象属性 ​

方法 ​

主要方法 ​

Nodes 集合方法 ​

TvwNode 对象方法 ​

事件 ​

代码示例 ​

基本用法 ​

处理事件 ​

动态节点加载 ​

查找节点 ​

常见用例 ​

文件系统浏览器 ​

组织架构图 ​

展开和折叠节点 ​

节点操作 ​

最佳实践 ​

其他提示 ​

TreeView 控件 (VBComCtlTreeView)

属性

主要属性

节点关系常量 (TvwNodeRelationshipConstants)

TvwNode 对象属性

方法

主要方法

Nodes 集合方法

TvwNode 对象方法

事件

代码示例

基本用法

处理事件

动态节点加载

查找节点

常见用例

文件系统浏览器

组织架构图

展开和折叠节点

节点操作

最佳实践

其他提示