主题：递归生成目录树的效率问题

Dim tr As WinForm.TreeView = e.Form.Controls("TreeView1")

tr.BuildTree("表A","生产单号|产品编码")

tr.Nodes.Add("生产单")
Dim btr As object = tr.baseControl
Dim nd As object = btr.Nodes("生产单")
For Each cnd As object In btr.Nodes
    If cnd.name <> nd.Name Then
        nd.Nodes.Add(cnd)
    End If
Next

 代码

 

Dim dt As DataTable = DataTables("表a")
e.Sender.StopRedraw
Dim pnd As WinForm.TreeNode = e.Node
For Each arys As String() In dt.GetValues("生产单号|产品编码", "", "生产单号,产品编码")
    If pnd.Name <> arys(0) Then
        pnd = e.Node.Nodes.Add(arys(0))
    End If
    pnd.Nodes.Add(arys(1))
Next
e.Sender.ResumeRedraw

 类似代码

 

 

Dim tr As WinForm.TreeView = e.Form.Controls("TreeView1")
Dim Nd = tr.Nodes.Add("生产单")

Dim dt As DataTable = DataTables("表a")

Dim nds As new List(Of WinForm.TreeNode)
For i As Integer = 0 To 3
    nds.Add(nd)
Next
For Each arys As String() In dt.GetValues("生产单号|产品编码|第七列", "", "生产单号,产品编码,第七列")
    Dim flag As Boolean = False
    For i As Integer = 0 To arys.Length - 1
        If nds(i+1).Name <> arys(i) OrElse flag Then
            flag = True
            nds(i+1) = nds(i).Nodes.Add(arys(i))
        End If
    Next
Next

'---在各表名下生成目录树节点
e.Sender.StopRedraw
Dim pnd As WinForm.TreeNode = e.Node
If e.Node.level = 1 Then  '如果是表名节点
    e.Node.Nodes.Clear  '清空原有节点
    Dim tbName As String = e.Node.Name
    Dim dr As DataRow = DataTables("表B").Find("表名 = '" & tbName & "'")
    If dr IsNot Nothing Then
        Dim Cols As String = dr("目录树列")
        Dim Cols_sort As String = Cols.replace("|",",")
            
        Dim nds As new List(Of WinForm.TreeNode)
        For i As Integer = 0 To Cols.Split("|").Length
            nds.Add(e.Node)
        Next
        For Each arys As String() In DataTables(tbName).GetValues(Cols, "", Cols_sort)
            Dim flag As Boolean = False
            For i As Integer = 0 To arys.Length - 1
                If nds(i+1).Name <> arys(i) OrElse flag Then
                    flag = True
                    nds(i+1) = nds(i).Nodes.Add(arys(i))
                End If
            Next
        Next
       
        e.Node.Expand
    End If
End If
e.Sender.ResumeRedraw

'---在各表名下生成目录树节点
e.Sender.StopRedraw
Dim pnd As WinForm.TreeNode = e.Node
If e.Node.level = 1 Then  '如果是表名节点
    e.Node.Nodes.Clear  '清空原有节点
    Dim tbName As String = e.Node.Name
    Dim dr As DataRow = DataTables("表B").Find("表名 = '" & tbName & "'")
    If dr IsNot Nothing Then
        Dim Cols As String = dr("目录树列")
        Dim Cols_sort As String = Cols.replace("|",",")
       
        Dim nds As new List(Of WinForm.TreeNode)
        For i As Integer = 0 To Cols.Split("|").Length
            nds.Add(e.Node)
        Next
        If nds.Count > 2 Then
            For Each arys As String() In DataTables(tbName).GetValues(Cols, "", Cols_sort)
                Dim flag As Boolean = False
                For i As Integer = 0 To arys.Length - 1
                    If nds(i+1).Name <> arys(i) OrElse flag Then
                        flag = True
                        nds(i+1) = nds(i).Nodes.Add(arys(i))
                    End If
                Next
            Next
        Else
            For Each arys As String In DataTables(tbName).GetValues(Cols, "", Cols_sort)
                nds(1) = nds(0).Nodes.Add(arys)
            Next
        End If
       
        e.Node.Expand
    End If
End If
e.Sender.ResumeRedraw

 buildTree就是单纯的递归，没什么异样。

 测试了下，速度也不是很慢，跟buildtree应该是差不了多少的啊