Dim dt As datatable = DataTables("单位树")
Dim dt2 As list(of DataRow)
Dim tr As WinForm.TreeView
Dim nd As WinForm.TreeNode
tr = e.Form.Controls("TreeView1")
dt2 = dt.Select(" [标题id] Like \'??\' ")
For Each dr1 As DataRow In dt2
    Dim str2 As String = dr1("标题id")
    Dim str3 As String = dr1("标题")
    nd = Tr.Nodes.Add(str2,str3)
    dt2 = dt.Select("[标题id] like \'"& str2 &"?? \' ")
   For Each dr2 As DataRow In dt2
        str2 = dr2("标题ID")
        str3 = dr2("标题")
        nd.Nodes.Add(str2,str3)
       dt2 =dt.Select("[标题id] like \'"& str2 &"?? \' ")
  Next
Next

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点击浏览该文件:管理项目9.rar

？不能作为通配符吧，你测试一下：

tr = e.Form.Controls("TreeView1")
dt2 = dt.Select(" [标题id] Like \'??\' ")
Messagebox.show(dt2.Count)

就会发现dt2的行数为0

如果只想筛选出只有两个字符的数据记录，代码要怎么写呀

并非要用Select的，在命令窗口执行：

For Each dr As DataRow In DataTables("单位树").DataRows
    dr("标题id") = dr("标题id").Trim()
Next
For Each dr1 As DataRow In DataTables("单位树").DataRows
    If dr1("标题id").Length = 2 Then
        Output.Show(dr1("标题id"))
        For Each dr2 As DataRow In DataTables("单位树").DataRows
            If dr2("标题id").StartsWith(dr1("标题id")) AndAlso dr2("标题id").Length = 4  Then
                Output.Show(dr2("标题id"))
                For Each dr3 As DataRow In DataTables("单位树").DataRows
                    If dr3("标题id").StartsWith(dr2("标题id")) AndAlso dr3("标题id").Length = 6  Then
                        Output.Show(dr3("标题id"))
                    End If
                Next
            End If
        Next
    End If
Next

其实这一段多余：

For Each dr As DataRow In DataTables("单位树").DataRows
    dr("标题id") = dr("标题id").Trim()
Next
之所以加上，是因为你输入不够严谨，标题ID后面都输入了空格的，01的长度不是2，而是3，后面有空格了。

领导如果这一则案例treeview 下一级是“无限延伸”（用户定义了三级，或者5级），那么如何生成呢。比如“华海仓库管理”中的参数设置窗口－－－单位树treeview，就是无限性的　延伸下级，同时又能根据数据记录生成treeview这个目录树

你就按照上面的代码，给他来个10级，代码也没有多长的。

10级的目录够深了。

这是一个任意层数的，不过一般用户理解起来比较困难：

Dim tr As WinForm.TreeView = e.Form.Controls("TreeView1")
Dim nd As WinForm.TreeNode
For Each dr As DataRow In DataTables("单位树").DataRows
    dr("标题id") = dr("标题id").Trim()
Next
tr.Nodes.Clear
Dim drs As List(of DataRow)
drs = DataTables("单位树").Select("", "标题ID")
For i As Integer = 0 To drs.Count -1
    If  drs(i)("标题id").Length = 2 Then
        nd = tr.nodes.Add(drs(i)("标题id"), drs(i)("标题id"))
    Elseif drs(i)("标题id").StartsWith(drs(i-1)("标题id")) Then
        nd = nd.nodes.Add(drs(i)("标题id"), drs(i)("标题id"))
    Else
        Do While True
            nd = nd.ParentNode
            If drs(i)("标题id").StartsWith(nd.Name)
                nd = nd.nodes.Add(drs(i)("标题id"), drs(i)("标题id"))
                Exit Do
            End If
        Loop
    End If
Next

删除节点又出了新的情况:

还是这一例，我使用了M版的方案，treeview生成了，但是删除节点又出了新的情况

  Dim tr As WinForm.TreeView
Dim nd As WinForm.TreeNode
tr = Forms("参数设置").Controls("TreeView1")
nd = tr.SelectedNode
If MsgBox("确认删除类型:" & nd.text & " ?",65,"提示") = 1 Then
Dim b  As String = nd.Name
b = b & "*"
    DataTables("单位树").DeleteFor("[标题id] like \'"& b &"\' ")
    nd.Remove
End If

实际没有删除、