求助：关于计算问题 - 专家坐堂 - Foxtable(狐表) - 新一代数据库软件，完美融合Access、Foxpro、Excel、vb.net之优势，人人都能掌握的快速软件开发工具!

求助：关于计算问题

此主题相关图片如下：额度计算求教.png

额度等于固定额度+临时额度

余额=收入-支出

可用额度=额度-（收入+支出）
特么感觉我的可用额度是不对的貌似计算方法不对

是不是应该是

第一条数据后可用额度是4400

那么第二条收入15597 那么可用额度应该是15597+4400 而不是4402

是不是我的思路出现了错误呢？

我是不是应该采用余额的代码写法来实现可用额度的计算呢？

当前表事件代码如下：

Select Case e.DataCol.Name

Case "固定额度","临时额度"

e.DataRow("额度")=e.DataRow("固定额度")+e.DataRow("临时额度")

Case "余额"

If e.DataRow("银行卡类别")="信用卡" Then

e.DataRow("可用额度")=e.DataRow("额度")-(e.DataRow("收入")+e.DataRow("支出"))

If e.DataRow("可用额度")<0 Then

MessageBox.Show("当前透支" & e.DataRow("可用额度") & "元")

End If

Case "收入","支出","银行卡卡号","额度"

Dim drs As List(of DataRow)

Dim Filter As String

Filter = "[_SortKey] >= " & e.DataRow("_SortKey") & "And [银行卡卡号] = '" & e.DataRow("银行卡卡号") & "'"

drs = e.DataTable.Select(Filter)

For Each dr As DataRow In drs

Filter = "[_SortKey] <= " & dr("_SortKey") & " And [银行卡卡号] = '" & e.DataRow("银行卡卡号") & "'"

Dim Val1 As Double = e.DataTable.Compute("Sum(收入)",Filter)

Dim Val2 As Double = e.DataTable.Compute("Sum(支出)",Filter)

dr("余额") = Val1 - Val2

If e.DataCol.Name = "银行卡卡号" AndAlso e.OldValue IsNot Nothing AndAlso e.OldValue <> e.NewValue Then

Filter = "[_SortKey] > " & e.DataRow("_SortKey") & " And [银行卡卡号] = '" & e.OldValue & "'"

drs = e.DataTable.Select(Filter)

For Each dr As DataRow In drs

Filter = "[_SortKey] <= " & dr("_SortKey") & " And [银行卡卡号]= '" & e.DataRow("银行卡卡号") & "'"

Dim Val1 As Double = e.DataTable.Compute("Sum(收入)",Filter)

Dim Val2 As Double = e.DataTable.Compute("Sum(支出)",Filter)

dr("余额") = Val1 - Val2

End If

End Select

烦请老师们多多指正，谢谢！

[此贴子已经被作者于2017/1/11 16:03:44编辑过]

1、先计算得出余额

2、可用额度，不就是等于额度+余额么？余额不是计算了收入和支出了么？

谢谢有点色老师已经解决了

采用了下列代码：

Select Case e.DataCol.Name

Case "固定额度","临时额度"

e.DataRow("额度")=e.DataRow("固定额度")+e.DataRow("临时额度")

Case "余额"

If e.DataRow("银行卡类别")="信用卡" Then

If e.DataRow("可用额度")<0 Then

MessageBox.Show("当前透支" & e.DataRow("可用额度") & "元")

End If

Case "收入","支出","银行卡卡号","额度"

Select Case e.DataCol.Name

Case "银行卡卡号","收入","支出"

Dim dr As DataRow

Dim mr As DataRow = e.DataRow

Dim drs As List(of DataRow)

dr = e.DataTable.Find("[_SortKey] < " & mr("_SortKey") & " And [银行卡卡号] = '" & mr("银行卡卡号") & "'", "[_SortKey] Desc")

If dr Is Nothing Then

mr("余额") = mr("收入") - mr("支出")

mr("可用额度") = mr("额度")+(mr("收入") - mr("支出"))

dr = mr

End If

drs = e.DataTable.Select("[_SortKey] >= " & dr("_SortKey") & " And [银行卡卡号] = '" & dr("银行卡卡号") & "'", "[_SortKey]")

For i As Integer = 1 To drs.Count - 1

drs(i)("余额") = drs(i-1)("余额") + drs(i)("收入") - drs(i)("支出")

drs(i)("可用额度") = drs(i-1)("可用额度") + drs(i)("收入") - drs(i)("支出")

If e.DataCol.Name = "银行卡卡号" AndAlso e.OldValue IsNot Nothing AndAlso e.OldValue <> e.NewValue Then

dr = e.DataTable.Find("[_SortKey] < " & mr("_SortKey") & " And [银行卡卡号] = '" & e.OldValue & "'", "[_SortKey] Desc")

If dr Is Nothing Then

dr = e.DataTable.Find("[银行卡卡号] = '" & e.OldValue & "'", "[_SortKey]")

If dr IsNot Nothing Then

dr("余额") = dr("收入") - dr("支出")

End If

If dr IsNot Nothing Then

drs = e.DataTable.Select("[_SortKey] >= " & dr("_SortKey") & " And [银行卡卡号] = '" & dr("银行卡卡号") & "'", "[_SortKey]")

For i As Integer = 1 To drs.Count - 1

drs(i)("余额") = drs(i-1)("余额") + drs(i)("收入") - drs(i)("支出")

drs(i)("可用额度") = drs(i-1)("可用额度") + drs(i)("收入") - drs(i)("支出")

End If

End Select

[此贴子已经被作者于2017/1/11 16:34:41编辑过]

主题：求助：关于计算问题