主题：语法解法

'用代码批量生成[根目录]
Dim ary1() = {"产品","客户","雇员"}

Dim trv As WinForm.TreeView = e.Form.Controls("TreeView1")
Dim nd As WinForm.TreeNode
trv.nodes.Clear
Dim dt As DataTable
Dim cmd As new SQLCommand
For i As Integer = 0 To ary1.length-1
    nd=trv.nodes.Add(Ary1(i))
    Select Case nd.name
        Case "产品"
            cmd.CommandText="select distinct 产品 from {订单}"
            dt=cmd.ExecuteReader
            For Each dr As DataRow In dt.DataRows
                nd.nodes.add(dr("产品"))
            Next
        Case "客户"          
            Dim ary2() = {"外部","内部"}
            For i1 As Integer = 0 To ary2.length-1
                nd.nodes.add(ary2(i1))
            Next
    End Select
Next