主题：自定义加载数的条件代码问题！！

窗口的AfterLoad事件代码如下：

Dim cmd As New SQLCommand
Dim dt As DataTable
cmd.C
cmd.CommandText = "SELECT DISTINCT Year(日期) As 年, Month(日期) As 月, 外协完成, 外协厂名称 From {外协管理}"
dt = cmd.ExecuteReader()
Dim trv As WinForm.TreeView = e.Form.Controls("TreeView1")
trv.BuildTree(dt,"年|月|外协完成|外协厂名称")
trv.Nodes.Insert("加载所有数据",0)

'加载第一页数据
With DataTables("外协管理")
    .LoadFilter = "" '清除加载条件
    .LoadPage = 0 '加载第一页
    .LoadTop = 500 '每页500行
    .Load()
    e.Form.Controls("TextBox2").Value = 1 & "/" & .TotalPages
End With

加载数的代码不知道该如何写了。。主要是外协厂名称这个条件不知道该如何添加了！！

Dim Filter As String

If e.Node.Text = "加载所有数据" Then
    Filter = ""
Else 
    Dim dr As DataRow = e.Node.DataRow '获取生成此节点的行
    Dim Year As Integer = dr("年")
    Dim Month As Integer = dr("月")
    Dim Product As String = dr("外协完成")
   
    Select Case e.Node.Level
        Case 0
            Filter ="Year(日期) = " & Year
        Case 1
            Filter ="Year(日期) = " & Year & " And Month(日期) = " & Month
        Case 2
            Filter ="Year(日期) = " & Year & " And Month(日期) = " & Month & " And 外协完成 = '" & Product & "'"
            End Select
End If

With DataTables("外协管理")
    .LoadFilter = Filter
    .LoadPage = 0
    .LoadTop = 500
    .Load()
    e.Form.Controls("TextBox2").Value = 1 & "/" & .TotalPages
End With