Dim dr1 As DataRow = DataTables("北仑申通菜鸟面单记录表").sqlfind("编号= '" & dr("内部单号") & "'")
Dim dr11 As DataRow = DataTables("北仑邮政小包普货面单信息导入").SQLFind("订单号='" & dr("内部单号") & "'")
Dim dr111 As DataRow = DataTables("北仑欧阳安能快递订单表").SQLFind("订单编号='" & dr("内部单号") & "'")
要判断 dr1, dr11, dr11中, 若有>=2个不是 nothing, 则跳出messagebox.show(""), 前面的条件判断怎么写表达式呢?