主题：目录树-递归

Dim tr As WinForm.TreeView = e.Form.Controls("TreeView1")
Dim rts() As String = {"全部","第100章","第200章","第300章","第400章","第500章","第600章","第700章"}
Dim nd As WinForm.TreeNode
Dim dt As DataTable = DataTables("工程量清单")
tr.StopRedraw()
tr.Nodes.Clear
For Each rt As String In rts
    tr.Nodes.Add(rt)
Next
For Each dr As DataRow In dt.Select("","子目号")
    If dr.IsNull("子目号") = False AndAlso dr("子目号").Length = 3   Then
        Dim i As Integer = CInt(dr("子目号").Substring(0,1))
        nd = tr.Nodes(i).Nodes.Add(dr("子目号"),dr("子目号") & " " & dr("子目名称"))
        Functions.Execute("AddChildren",nd,dt)
    End If
Next
tr.ResumeRedraw()以前代码是这样的，现在想加一个节点，就是”项目编号“