请问如何确定两个日期之间有几个星期一？ - 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!

修正一下:

Dim dt1 As Date = #6/3/2013#

Dim dt2 As Date = #6/24/2013#

Dim dt As Date

Dim cnt As Integer

For i As Integer = 0 To (dt2-dt1).TotalDays

dt = dt1.AddDays(i)

If dt.DayOfWeek = 1 Then

cnt = cnt + 1

End If

output.show("老大低效率但準確的 ===> " & cnt)

'===============================

Dim n1 As Integer

Dim d1,d2 As Date

n1 =dt1.DayOfWeek

d1 = dt1.addDays(1-n1 )

d2 = dt2.addDays(1-n1)

n1 = Int(((d2-d1).TotalDays+1)/7)+1

n1+=iif(dt2.DayOfWeek =0,-1,0)

output.show("測試高效率的 ===> " & n1)

以下是引用don在2013-5-31 17:36:00的发言：

=====================

這太低效了吧!

Dim dt1 As Date = #1/1/2000#

Dim dt2 As Date = #12/1/2012#

Dim n1 As Integer

n1 =dt1.DayOfWeek

dt1 = dt1.addDays(1-n1 )

dt2 = dt2.addDays(1-n1)

n1 = Int(((dt2-dt1).TotalDays+1)/7)+1

If dt2.DayOfWeek = 1 Then n1+=1

Output.Show(n1)

==================================================

测试上面的代码结果不正确，修改如下：

Dim dt1 As Date = #6/1/2013#
Dim dt2 As Date = #6/17/2013#
Dim n1,n As Integer

n1 =dt1.DayOfWeek
dt1 = dt1.addDays((8-n1) Mod 7)
n = Int(((dt2-dt1).TotalDays)/7)+1

Output.Show(n)

'可以将dt1和dt2修改成周一、周日、周二这种有代表性的值进行测试，看看结果与日历上的是否一致

呵呵，我觉得学习编程越来越有意思了！

非常感谢！！

以下是引用傻马难骑在2013-6-1 14:41:00的发言：

Dim dt1 As Date = #6/1/2013#
Dim dt2 As Date = #6/17/2013#
Dim n1,n As Integer

n1 =dt1.DayOfWeek
dt1 = dt1.addDays((8-n1) Mod 7)
n = Int(((dt2-dt1).TotalDays)/7)+1

Output.Show(n)

'可以将dt1和dt2修改成周一、周日、周二这种有代表性的值进行测试，看看结果与日历上的是否一致

==============================================

高!學習!!在你的基礎上改為更通用的:求星期一至星期日

1	===>	星期一
2	===>	星期二
3	===>	星期三
4	===>	星期四
5	===>	星期五
6	===>	星期六
7	===>	星期日

'求星期六:

Dim dt1 As Date = #5/1/2013#

Dim dt2 As Date = #5/31/2013#

Dim n1,n2,n3,i As Integer

i = 6 '求星期六: 1-7分別對應星期一至星期日

n1 =dt1.DayOfWeek

dt1 = dt1.addDays((7+i-n1) Mod 7)

n2 = Int((dt2-dt1).TotalDays/7)+1

Output.Show(n2)

'求本月有幾個雙休日

Dim n1,n2,i As Integer

Dim dt1 ,dt2 As Date

dt1 = Date.Today

dt1 =New date(dt1.year,dt1.Month,1)

dt2 =New date(dt1.year,dt1.Month,Date.DaysinMonth(dt1.year,dt1.Month))

i = 6

n1 =dt1.DayOfWeek

dt1 = dt1.addDays((7+i-n1) Mod 7)

n2 = Int((dt2-dt1).TotalDays/7)+1

i =7

dt1 = dt1.addDays((7+i-n1) Mod 7)

n2+ = Int((dt2-dt1).TotalDays/7)+1

Output.Show(n2)

[此贴子已经被作者于2013-6-3 18:49:43编辑过]

主题：请问如何确定两个日期之间有几个星期一？