AfterLoad事件改为:
Dim tr As WinForm.TreeView = e.Form.Controls("TreeView1")
tr.BuildTree("表4", "类别|项目")
Dim s As String = e.Form.DropDownBox.Value
Dim nms As new List(of String)
Dim trv As WinForm.TreeView = e.Form.Controls("TreeView1")
If s > "" Then
nms.AddRange(s.Split(","))
End If
For Each nd As WinForm.TreeNode In trv.AllNodes
nd.Checked = nms.Contains(nd.text)
Next