主题：[求助]

Select Case e.DataCol.Name
    Case "上游客户","品牌","商品车","上游动态","计划下达时间"
        Dim dr As DataRow = e.DataRow
        Dim pr As DataRow
        If dr.IsNull("上游客户") OrElse dr.IsNull("品牌") OrElse dr.IsNull("商品车") OrElse dr.IsNull("上游动态") OrElse dr.IsNull("计划下达时间") Then
            dr("上游运输单价") = Nothing
        Else
            Dim filter As String
            filter = "上游客户 = '" & dr("上游客户") & "' And 品牌 = '" & dr("品牌") & "'And 上游动态 = '" & dr("上游动态") & "' And 商品车 = '" & dr("商品车") & "'And 计划下达时间 BETWEEN '" & dr("起始日期") And dr("终止日期") & "'"
            pr = DataTables("上游运价表").Find(filter)
            If pr IsNot Nothing Then
                dr("上游运输单价") = pr("单台单价")
            End If
        End If
End Select

想实现跨表引用，问题出在了：And 计划下达时间 BETWEEN '" & dr("起始日期") And dr("终止日期") &这段上，没加这段是可引用的，加上这句后就代不出数据了

请老师指导