在日期範圍內插入星期幾的記錄

Question

我想弄清楚如何做到這一點。一直在做研究，找不到任何東西，我可以弄清楚如何使用。

我有一個開始日期，結束日期，recurringday，客戶

開始日期= 2013年4月1日

結束日期= 2013年4月30日

客戶=約翰

recurringday =週一

我想在startdate和enddate中每個星期一插入一條約翰的記錄，有人可以幫我嗎？新到VB.NET

感謝

Answer 1

使用DAYOFWEEK函數來檢查，如果今天的天是星期一。然後使用插入命令。

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建議.DayofWeek，但我不知道他的方法滿足您的要求。試試這個：

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

試試這個。

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