主题：为什么没有触发这一段代码？

如果不行，就说明没有符合条件的行：

Dim dr As DataRow = e.DataRow
If e.DataCol.Name = "市场片区_省市" Orelse e.DataCol.Name = "市场片区_县市" Then
    If dr.IsNull("市场片区_省市") Orelse dr.IsNull("市场片区_县市")  Then
        Return
    Else
        Dim a As new SQLCommand
        Dim b As datatable
        With a
            .C
            .CommandText = "select * from {行政区域} where [省市] = '"& dr("市场片区_省市") & "' and [县市] = '" & dr("市场片区_县市") &"' "
            b = .ExecuteReader
        End With
        If b.DataRows.Count = 0 Then
            dr("市场片区_县市") = Nothing
            dr("营销部代码") = Nothing
            MessageBox.Show("县市你改过了吗?")
        Else
            Dim sss As String
            Dim xss As String
            sss = dr("市场片区_省市")
            xss = dr("市场片区_县市")
            sss = sss.SubString(0,2)
            xss = xss.SubString(0,2)
            sss = getpy(sss,True)
            xss = getpy(xss,True)
            dr("营销部代码") = sss & xss
        End If
    End If
End If