主题：关于设置信用卡还款日

不需要计算。直接填写还款日就好了啊

表结构

此主题相关图片如下：qq截图20180123101752.png

  

代码

Dim dt_xyk As DataTable = DataTables("信用卡")
Dim dt_lsz As DataTable = DataTables("流水账")
Dim dt_dyyh As DataTable = DataTables("还款")
dt_dyyh.DataRows.Clear
Dim d As Date = new Date(Date.Today.Year, Date.Today.Month, 1)
Dim ds() As Date = {d, d.AddMonths(1)}
d = d.AddMonths(-1)
For Each dr As DataRow In dt_xyk.DataRows
    Dim ndr As DataRow = dt_dyyh.AddNew
    ndr("账户名称") = dr("账户名称")
    ndr("账单日") = d.AddDays(dr("账单日")-1)
    ndr("转出") = dt_lsz.Compute("sum(金额)", "账户名称 = '" & ndr("账户名称") & "' and 日期 < #" & ndr("账单日") & "# and 类别 = '转出'")
    ndr("转入") = dt_lsz.Compute("sum(金额)", "账户名称 = '" & ndr("账户名称") & "' and 日期 < #" & ndr("账单日") & "# and 类别 = '转入'")
    ndr("信用额度") = dr("信用额度")
    ndr("当月应还") = ndr("转出") - ndr("转入")
    ndr("可用额度") = ndr("信用额度") - ndr("当月应还")
    If dr.IsNull("还款日") OrElse dr.IsNull("n日后还款") = False Then
        ndr("还款日") = cdate(ndr("账单日")).AddDays(dr("n日后还款"))
    Else
        If val(dr("还款日")) < val(dr("账单日")) Then
            ndr("还款日") = d.AddDays(dr("还款日")-1).AddMonths(1)
        Else
            ndr("还款日") = d.AddDays(dr("还款日")-1)
        End If
    End If
    If ndr("当月应还") > 0 Then
        If ndr("还款日") > Date.Today Then
            ndr("账单状态") = "已出账,没还款"
        Else
            ndr("账单状态") = "已出账,逾期还款"
        End If
    End If
    ndr("账单月份") = Format(d, "yyyyMM")
Next
For Each d In ds
    For Each dr As DataRow In dt_xyk.DataRows
        Dim ndr As DataRow = dt_dyyh.AddNew
        ndr("账户名称") = dr("账户名称")
        ndr("账单日") = d.AddDays(dr("账单日")-1)
        ndr("转出") = dt_lsz.Compute("sum(金额)", "账户名称 = '" & ndr("账户名称") & "' and 日期 >= #" & ndr("账单日").addmonths(-1) & "# and 日期 <= #" & ndr("账单日") & "# and 类别 = '转出'")
        ndr("转入") = dt_lsz.Compute("sum(金额)", "账户名称 = '" & ndr("账户名称") & "' and 日期 >= #" & ndr("账单日").addmonths(-1) & "# and 日期 >= #" & ndr("账单日") & "# and 类别 = '转入'")
        Dim yq_out = dt_lsz.Compute("sum(金额)", "账户名称 = '" & ndr("账户名称") & "' and 日期 < #" & ndr("账单日").addmonths(-1) & "# and 类别 = '转出'")
        Dim yq_in = dt_lsz.Compute("sum(金额)", "账户名称 = '" & ndr("账户名称") & "' and 日期 < #" & ndr("账单日").addmonths(-1) & "# and 类别 = '转入'")
        ndr("信用额度") = dr("信用额度")
        ndr("当月应还") = ndr("转出") - ndr("转入")
        ndr("可用额度") = ndr("信用额度") - ndr("当月应还") - yq_out + yq_in
        If dr.IsNull("还款日") OrElse dr.IsNull("n日后还款") = False Then
            ndr("还款日") = cdate(ndr("账单日")).AddDays(dr("n日后还款"))
        Else
            If val(dr("还款日")) < val(dr("账单日")) Then
                ndr("还款日") = d.AddDays(dr("还款日")-1).AddMonths(1)
            Else
                ndr("还款日") = d.AddDays(dr("还款日")-1)
            End If
        End If
        If ndr("当月应还") > 0 Then
            If ndr("账单日") > Date.Today Then
                ndr("账单状态") = "未出账,没还款"
            Else
                ndr("账单状态") = "已出账,没还款"
            End If
        Else
            If ndr("账单日") > Date.Today Then
                ndr("账单状态") = "未出账,没还款"
            Else
                ndr("账单状态") = "已出账,已还款"
            End If
        End If
        ndr("账单月份") = Format(d, "yyyyMM")
    Next
Next

列名，类型，你改成什么随意。只要你代码对应即可。