感谢老师耐心指导 我研究出来 在你的思路下 我加了几个代码 实现了
此主题相关图片如下：加权平均价好了.png
If e.DataCol.name = "销售数量"
Dim oldCount As Integer = e.DataTable.Compute("sum(销售数量)","货号='" & e.DataRow("货号") & "' and 日期 < #" & e.DataRow("日期") & "#")
Dim oldCount1 As Double = e.DataTable.Compute("sum(销售成本)","货号='" & e.DataRow("货号") & "' and 日期 < #" & e.DataRow("日期") & "#")
Dim cnt As Integer = 0
Dim c1 As Integer = 0
Dim c2 As Integer = 0
Dim csum As Double = 0
Dim csum1 As Double = 0
Dim csum2 As Double = 0
Dim drs As List(of DataRow) = DataTables("采购").Select("货号='" & e.DataRow("货号") & "' and 日期 <= #" & e.DataRow("日期") & "#","日期")
Dim idx As Integer = -1
For i As Integer = 0 To drs.count - 1
cnt += drs(i)("数量")
csum +=drs(i)("数量")*drs(i)("单价")
If cnt >= oldCount Then
idx = i
Exit For
End If
Next
If idx > -1
Dim dr As DataRow = drs(idx)
c1 = cnt - oldCount
csum1 =csum-oldCount1
For j As Integer = idx+1 To drs.count - 1
dr = drs(j)
c2 = dr("数量")
csum2 = c2*dr("单价")
csum1 += csum2
c1 += c2
Next
e.DataRow("平均价格") = csum1 / c1
End If
End If
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Post By：2019/8/31 11:26:00 [显示全部帖子]
，我是原来 把旧数据销售数量删掉重新输的数量不行 必须的重置列就好了O(∩_∩)O哈哈~ 那我自己设置一个切换表重置列让它自动
