VB.Net - 如何在展开和折叠匹配（或不匹配）搜索字符串的节点的所有 TreeView 节点中动态搜索字符串？

VB.Net - How to dynamicaly search for a string in all TreeView nodes expanding and collapsing nodes matching (or not) the search string?

提问by Daniel Santos

I′m trying to implement dynamic search on a treeview component, and I′m almost done with it, except that since it′s a dynamic search based on the textchanged event of a textbox, the first characters of the search string are always found, so the search function expand all nodes because they are a valid match.

我正在尝试在树视图组件上实现动态搜索，我几乎完成了它，除了因为它是基于文本框的 textchanged 事件的动态搜索，所以总是找到搜索字符串的第一个字符，因此搜索功能会扩展所有节点，因为它们是有效匹配项。

The thing is that as the search string becomes more complete, those nodes that were expanded when they had a match, now needs to be collapsed because they no longer match the search string... and this is not happening... I could not find yet a way to collapse and expand the nodes dinamically as the search string changes...

问题是，随着搜索字符串变得更加完整，那些在匹配时展开的节点现在需要折叠，因为它们不再匹配搜索字符串……而这没有发生……我不能找到一种随着搜索字符串更改而动态折叠和扩展节点的方法......

I have uploaded a video and the Visual Studio 2012 solution so you can take a look at it and see where I′m dropping the ball...

我上传了一个视频和 Visual Studio 2012 解决方案，所以你可以看看它，看看我在哪里丢球......

This is the code of my function that does the search: (You can see in the video it works as expected, so my problem is the expanding/collapsing of the nodes as they match(or not) the search string.

这是我执行搜索的函数的代码：（您可以在视频中看到它按预期工作，所以我的问题是节点在匹配（或不匹配）搜索字符串时展开/折叠。

I′ve implemented some ideas in the "FindRecursive" function to collapse and expand the nodes, but it′s not working as expected. I managed to even put the control in an infinite loop due to my wrong logic.

我已经在“FindRecursive”函数中实现了一些想法来折叠和扩展节点，但它没有按预期工作。由于我的错误逻辑，我什至设法将控件置于无限循环中。

Any help will be very appreciated,

任何帮助将不胜感激，

Tks!

太棒了！

Video showing the problem

显示问题的视频

Visual Studio 2012 Project + Test File

Visual Studio 2012 项目 + 测试文件

Private Sub txtFiltroIDs_TextChanged(sender As Object, e As EventArgs) Handles txtFilterToolIDs.TextChanged
        ClearBackColor()
        FindByText()
    End Sub

    Private Sub FindByText()
        Dim nodes As TreeNodeCollection = tviewToolIDs.Nodes
        Dim n As TreeNode
        For Each n In nodes
            FindRecursive(n)
        Next
    End Sub

    Private Sub FindRecursive(ByVal tNode As TreeNode)
        If txtFilterToolIDs.Text = "" Then
            tviewToolIDs.CollapseAll()
            tviewToolIDs.BackColor = Color.White
            ExpandToLevel(tviewToolIDs.Nodes, 1)
        Else
            Dim tn As TreeNode
            For Each tn In tNode.Nodes
                ' if the text properties match, color the item
                If tn.Text.Contains(txtFilterToolIDs.Text) Then
                    tn.BackColor = Color.Yellow
                    tn.EnsureVisible()        'Scroll the control to the item
                End If

                FindRecursive(tn)
            Next
        End If
    End Sub

    Private Sub ClearBackColor()
        Dim nodes As TreeNodeCollection
        nodes = tviewToolIDs.Nodes
        Dim n As TreeNode
        For Each n In nodes
            ClearRecursive(n)
        Next
    End Sub

    Private Sub ClearRecursive(ByVal treeNode As TreeNode)
        Dim tn As TreeNode
        For Each tn In treeNode.Nodes
            tn.BackColor = Color.White
            ClearRecursive(tn)
        Next
    End Sub

采纳答案by Idle_Mind

Following my initial comments, try something like:

按照我最初的评论，尝试以下操作：

Private Sub txtFiltroIDs_TextChanged(sender As Object, e As EventArgs) Handles txtFilterToolIDs.TextChanged
    tviewToolIDs.BeginUpdate()
    tviewToolIDs.CollapseAll()
    ClearBackColor()
    FindByText()
    tviewToolIDs.EndUpdate()
    tviewToolIDs.Refresh()
End Sub