狐表老师好，买入平均价列在增加行时不添加平均值数据。（我是在窗口关联表中输入数据的）

Select Case e.DataCol.name
    Case "买入价","买入量","卖出价","卖出量"
        Dim filter As String = "股票名称=\'" & e.DataRow("股票名称") & "\'"
        Dim sum1 As Double = 0
        Dim sum2 As Double = 0
        Dim count1 As Double = 0
        Dim count2 As Double = 0
        Dim pinavg As Double = 0
        For Each dr As DataRow In e.DataTable.Select(filter, "_sortkey")
            sum1 += dr("买入价") * dr("买入量")
            sum2 += pinavg * dr("卖出量")
            count1 += dr("买入量")
            count2 += dr("卖出量")
            If dr.IsNull("卖出价") Then
                dr("买入平均价") = (sum1-sum2) / (count1-count2)
                dr("卖出均价") = Nothing
                pinavg = dr("买入平均价")
            Else
                dr("买入平均价") = Nothing
            End If
        Next
End Select

 参考 http://www.foxtable.com/help/topics/1587.htm