If nd IsNot Nothing Then
If nd.Level = 5 Then
MessageBox.Show("最多允许三层节点!","提示",MessageBoxButtons.OK,MessageBoxIcon.Information)
Else
Dim dr As DataRow = DataTables("表A").AddNew
If nd.Level = 0 Then
dr("大类") = nd.Text
dr("二类") = "新节点"
ElseIf nd.Level = 1
dr("大类") = nd.ParentNode.Text
dr("二类") = nd.text
dr("三类") = "新节点"
ElseIf nd.Level = 2
dr("大类") = nd.ParentNode.ParentNode.Text
dr("二类") = nd.ParentNode.Text
dr("三类") = nd.text
dr("4类") = "新节点"
ElseIf nd.Level = 3
……
……
End If
nd = nd.Nodes.Add("新节点")
tr.SelectedNode = nd
tr.Select()
tr.BeginEdit()
End If
End If