vb.net - 在日期范围内插入星期几的记录

Question

我试图弄清楚如何做到这一点。一直在研究，找不到任何我可以弄清楚如何使用的东西。

我有一个开始日期、结束日期、重复日期、客户

开始日期 = 04/01/2013

结束日期 = 04/30/2013

客户 = 约翰

重复日=星期一

我想在每个星期一的 startdate 和 enddate 内为 john 插入一条记录，有人可以帮我吗？vb.net 的新手

谢谢

Answer 1

使用 DayofWeek 函数检查今天是否是星期一。然后使用插入命令。

Dim startdate As DateTime = Convert.ToDateTime("01 Apr 2013")
Dim enddate As DateTime = Convert.ToDateTime("30 Apr 2013")

Dim DofW = Now.DayOfWeek()
dim recurringday = "Monday"

If now >= startdate And now <= enddate Then
  If DofW = recurringday Then
    'Insert Record
  End If
End If

Answer 2

@Sweety 建议使用 .DayofWeek，但我不确定他的方法是否满足您的要求。尝试这个：

    Dim StartDate As DateTime = CDate("01 Apr 2013")
    Dim FinishDate As DateTime = CDate("30 Apr 2013")

    Dim RecurringDay = "Monday"

    Dim Period = FinishDate.Subtract(StartDate).TotalDays

    Dim CurrentDate As DateTime

    For Counter As Integer = 0 To Period
        CurrentDate = StartDate.AddDays(Counter)
        If CurrentDate.DayOfWeek = RecurringDay Then
            'Insert Record
        End If
    Next

Answer 3

尝试这个。

    Dim StartDate As DateTime = #4/1/2013#
    Dim FinishDate As DateTime = #4/30/2013#

    Dim RecurringDay As Integer = DayOfWeek.Monday

    'force to first RecurringDay
    If RecurringDay < StartDate.DayOfWeek Then StartDate = StartDate.AddDays(7)
    StartDate = StartDate.AddDays(RecurringDay - StartDate.DayOfWeek)

    Do While StartDate <= FinishDate
        Debug.WriteLine(StartDate.ToLongDateString)
        'insert record
        StartDate = StartDate.AddDays(7)
    Loop