主题：[求助]跨表查累计数计算当月数的问题

大哥好 小弟对现实中求当月专项附加扣除数做了一个简化模拟 抄文档改了上半段 下半段抄另外一块文档已经没方向了。。。 还请蓝大出手相助 先谢谢您啦

寻找 表C（“累计金额”），条件：表C（“单位”、“日期”、“姓名”）= 表B当前行（“单位”、“日期”、“姓名”）

当表B（“单位”+“姓名”）第一次出现时，时表B（当月金额）= 表C（累计金额）（注找不到时表C（累计金额）算作0）。

当表B（“单位”+“姓名”）不是第一次出现时，表B（当月金额）= 表C（累计金额）- 表b（当月金额合计数，条件：单位等于当前行单位、且姓名等于当前行姓名）（注找不到时表C（累计金额）算作0）

Select Case e.DataCol.Name
    Case "单位","日期","姓名","当月金额"
        
        Dim mr As DataRow = e.DataRow
        
        Dim dr1 As DataRow
        dr1 = DataTables("表C").Find("[单位] = '" & mr("单位") & "' And [日期] = #" & mr("日期") & "# And [姓名] = '" & mr("姓名") & "'")
        
        Dim dr2 As DataRow
        dr2 = e.DataTable.Find("[_SortKey] < " & mr("_SortKey") & " And [单位] = '" & mr("单位") & "' And [姓名] = '" & mr("姓名") & "'", "[_SortKey] Desc")
        If dr2 Is Nothing Then
            If dr1 Is Nothing Then
                mr("当月金额") = Nothing
            Else
                mr("当月金额") = dr1("累计金额")
            End If
            dr2 = mr
        End If
        
        Dim drs As List(of DataRow)
        Dim Filter As String
        drs = e.DataTable.Select("[_SortKey] >= " & dr2("_SortKey") & " And [单位] = '" & dr2("单位") & "' And [姓名] = '" & dr2("姓名") & "'", "[_SortKey]")
        For Each dr3 As DataRow In drs
            Dim Val1 As Double = e.DataTable.Compute("Sum(当月金额)"," [单位] = '" & dr3("单位") & "' And [姓名] = '" & dr3("姓名") & "'")
            mr("当月金额") = dr1("累计金额") - Val1
        Next
End Select

else

 蓝大好 测试了下 这样可以满足需求了 谢谢您啦  今天我再测试最后一个个调税 搞完后 来分享一下用foxtable一起核算多加公司工资的思路

Select Case e.DataCol.Name
    Case "单位","日期","姓名","当月金额"
        
        Dim mr As DataRow = e.DataRow
        
        Dim dr1 As DataRow
        dr1 = DataTables("表C").Find("[单位] = '" & mr("单位") & "' And [日期] = #" & mr("日期") & "# And [姓名] = '" & mr("姓名") & "'")
        
        Dim dr2 As DataRow
        dr2 = e.DataTable.Find("[_SortKey] < " & mr("_SortKey") & " And [单位] = '" & mr("单位") & "' And [姓名] = '" & mr("姓名") & "'", "[_SortKey] Desc")
        If dr2 Is Nothing Then
            If dr1 Is Nothing Then
                mr("当月金额") = 0
            Else
                mr("当月金额") = dr1("累计金额")
            End If
            dr2 = mr
        End If
        
        
        Dim drs As List(of DataRow)
        Dim Filter As String
        drs = e.DataTable.Select("[_SortKey] >= " & dr2("_SortKey") & " And [单位] = '" & dr2("单位") & "' And [姓名] = '" & dr2("姓名") & "'", "[_SortKey]")
        For i As Integer = 1 To drs.Count - 1
            dr2 = drs(i)
            dr1 = DataTables("表C").Find("[单位] = '" & dr2("单位") & "' And [日期] = #" & dr2("日期") & "# And [姓名] = '" & dr2("姓名") & "'")
            Dim Val1 As Double = e.DataTable.Compute("Sum(当月金额)"," [单位] = '" & dr2("单位") & "' And [姓名] = '" & dr2("姓名") & "' and [_SortKey] <" & dr2("_SortKey"))
            If dr1 Is Nothing Then
                dr2("当月金额") = 0 - Val1
            Else
                dr2("当月金额") = dr1("累计金额") - Val1
            End If
        Next
        
End Select