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vb.net - 递归地将 ZIP 文件结构转换为树视图

问题描述

我一直想知道是否有办法让我的代码以递归方式运行。

我确实在 Stack Overflow 上看过一些示例，但它们似乎都只处理本地驱动器上的现有文件结构。

Zip 文件没有文件结构。只有完整路径的列表。

在我因为没有发布任何编码尝试而受到抨击之前，我不知道该怎么做。递归是一种巫术魔法，如果没有示例工作，我永远无法正确编码。

以下是我制定的解决方案。如果有人一直试图解决这个问题..试试这个。它可以工作，但只能处理 8 层嵌套。一旦您了解了代码的工作原理，它就可以很容易地扩展。

如果可以将其转换为更紧凑且可能更快的东西，我想尝试在一些指导下对其进行编码。

Module modZipFolderResolver
Public root As root_
Public Structure root_
    Public node() As root_
    Public name As String
    Public index As Integer
    Public isDir As Boolean
    Public count As Integer
    Dim n As TreeNode
    Public Function find(f As String, ByRef idx As Integer)
        If node Is Nothing Then
            Return False
        End If
        For k = 0 To Me.node.Length - 1
            If node(k).name = f Then
                idx = k
                Return True
            End If
        Next
        Return False
    End Function
    Public Sub add(ByRef s As String, ByRef idx As Integer, ByVal fullname As String, ByRef p_node As TreeNode, ByVal isDir As Boolean)
        ReDim Preserve Me.node(Me.count + 1)
        idx = Me.count
        node(Me.count) = New root_
        node(Me.count).name = s
        '------------------------------------
        'add node
        Dim nn As New TreeNode 'create new treevire node
        nn.Tag = fullname
        nn.Text = Me.node(Me.count).name
        If isDir Then ' set image index based on type
            Me.node(Me.count).isDir = True
            nn.SelectedImageIndex = 2
            nn.ImageIndex = 2
            nn.Name = "dir" 'used for evauation when clicked
        Else
            Me.node(Me.count).isDir = False
            nn.SelectedImageIndex = 1
            nn.ImageIndex = 0
            nn.Name = ""
        End If
        '------------------------------------
        ' make a new one if its blank
        If p_node Is Nothing Then
            p_node = New TreeNode
            p_node.Text = Me.name
        End If
        Me.node(Me.count).n = New TreeNode
        Me.node(Me.count).n = nn
        p_node.Nodes.Add(Me.node(Me.count).n)
        '------------------------------------
        Me.count += 1
    End Sub
End Structure

Public Sub build_tree()
    '--------------------------------------------------------
    'create the root node
    root = New root_
    GC.Collect() ' clean up garbage if we just killed existing data
    root.n = New TreeNode
    root.n.SelectedImageIndex = 2
    root.n.ImageIndex = 2
    root.n.Text = frmTreeList.tv_filenames.SelectedNode.Text
    root.n.Name= "dir"
    frmTreeList.tv_contents.Nodes.Add(root.n) 'Add to treeview
    '--------------------------------------------------------
    'now the fun up part. Create the nested tree structure.
    Dim indexes(9) As Integer 'used to keep track of where we are in the tree structure
    Dim isDir As Boolean = False ' flag for setting up image index
    For Each ent In current_package
        Dim ext = Path.GetExtension(ent.FileName)
        If ext.Length > 0 Then 'is this entry a file or directory?
            isDir = False
        Else
            isDir = True
        End If
        Dim a = ent.FileName.Split("/")
        For i = 0 To 8 ' 8 levels deep enough?
            If a.Length = 2 Then
                Exit For
            End If
            If i > a.Length - 1 Then
                Exit For
            End If
            For k = i To a.Length - 1
                If a(k) = "" Then
                    Exit For
                End If
                Dim idx As Integer
                Select Case k
                    Case 0
                        If root.find(a(0), idx) Then
                            indexes(0) = idx
                        Else
                            root.add(a(0), idx, ent.FileName, root.n, isDir)
                            indexes(0) = idx
                            Exit For
                        End If
                    Case 1
                        If root.node(indexes(0)).find(a(1), idx) Then
                            indexes(1) = idx
                        Else
                            Dim n = root.node(indexes(0)).n
                            root.node(indexes(0)).add(a(1), idx, ent.FileName, n, isDir)
                            indexes(1) = idx
                            Exit For
                        End If
                    Case 2
                        If root.node(indexes(0)).node(indexes(1)).find(a(2), idx) Then
                            indexes(2) = idx
                        Else
                            Dim n = root.node(indexes(0)).node(indexes(1)).n
                            root.node(indexes(0)).node(indexes(1)).add(a(2), idx, ent.FileName, n, isDir)
                            indexes(2) = idx
                            Exit For
                        End If
                    Case 3
                        If root.node(indexes(0)).node(indexes(1)).node(indexes(2)).find(a(3), idx) Then
                            indexes(3) = idx
                        Else
                            Dim n = root.node(indexes(0)).node(indexes(1)).node(indexes(2)).n
                            root.node(indexes(0)).node(indexes(1)).node(indexes(2)).add(a(3), idx, ent.FileName, n, isDir)
                            indexes(3) = idx
                            Exit For
                        End If
                    Case 4
                        If root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).find(a(4), idx) Then
                            indexes(4) = idx
                        Else
                            Dim n = root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).n
                            root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).add(a(4), idx, ent.FileName, n, isDir)
                            indexes(4) = idx
                            Exit For
                        End If
                    Case 5
                        If root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).find(a(5), idx) Then
                            indexes(5) = idx
                        Else
                            Dim n = root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).n
                            root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).add(a(5), idx, ent.FileName, n, isDir)
                            indexes(5) = idx
                            Exit For
                        End If
                    Case 6
                        If root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).node(indexes(5)).find(a(6), idx) Then
                            indexes(6) = idx
                        Else
                            Dim n = root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).node(indexes(5)).n
                            root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).node(indexes(5)).add(a(6), idx, ent.FileName, n, isDir)
                            indexes(6) = idx
                            Exit For
                        End If
                    Case 7
                        If root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).node(indexes(5)).node(indexes(6)).find(a(7), idx) Then
                            indexes(7) = idx
                        Else
                            Dim n = root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).node(indexes(5)).node(indexes(6)).n
                            root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).node(indexes(5)).node(indexes(6)).add(a(7), idx, ent.FileName, n, isDir)
                            indexes(7) = idx
                            Exit For
                        End If
                    Case 8
                        If root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).node(indexes(5)).node(indexes(6)).node(indexes(7)).find(a(8), idx) Then
                            indexes(8) = idx
                        Else
                            Dim n = root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).node(indexes(5)).node(indexes(6)).node(indexes(7)).n
                            root.node(indexes(0)).node(indexes(1)).node(indexes(2)).node(indexes(3)).node(indexes(4)).node(indexes(5)).node(indexes(6)).node(indexes(7)).add(a(8), idx, ent.FileName, n, isDir)
                            indexes(8) = idx
                            Exit For
                        End If
                End Select
            Next 'k
        Next 'i
    Next 'each ent
End Sub
End Module

此代码运行良好，并生成这样的树视图。我只是希望有人可以阐明可能使用递归来加快速度。 树视图图像

标签： vb.net

解决方案

就算法而言，我会这样做： -

对于每个路径： - 通过“/”字符将路径拆分为字符串数组。将此数组连同根节点和索引 0 一起传递到一个新函数中，以指示您要到达的位置。

该函数应该： - 获取传入的索引的路径分量 查找或在作为参数传入的节点内创建与路径分量匹配的子节点 如果传入的索引等于路径分量数组的长度 -1然后返回找到/创建的子节点否则该函数应返回对自身的调用结果，传入子节点和传入+1的索引

此函数应根据需要创建节点并返回路径的节点

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