計算一個月中的天數

Question

有沒有計算一個月內天數的方法？

Answer 1

是：

Const July As Integer = 7 
Const Feb As Integer = 2 

' daysInJuly gets 31. ' 
Dim daysInJuly As Integer = System.DateTime.DaysInMonth(2001, July) 

' daysInFeb gets 28 because the year 1998 was not a leap year. ' 
Dim daysInFeb As Integer = System.DateTime.DaysInMonth(1998, Feb) 

' daysInFebLeap gets 29 because the year 1996 was a leap year. ' 
Dim daysInFebLeap As Integer = System.DateTime.DaysInMonth(1996, Feb) 

幸得MSDN。

Answer 2

http://authors.aspalliance.com/aspxtreme/sys/DateTimeClassDaysInMonth.aspx

Public Shared Function DaysInMonth (_ 
    ByVal year As Integer, _ 
    ByVal month As Integer _ 
} As Integer 

Answer 3

Dim d As New DateTime(2010, 4, 1) 

Dim month As Integer = d.Month 

While d.Month = month 
    Console.WriteLine(d.[Date]) 
    d = d.AddDays(1) 
End While 

當然你可以改變的日期如何輸出對其進行格式化，以你的意志。

Answer 4

使用數組：[31,28,31,30,31,30,31,31,30,31,30,31] 如果（year mod 400 = 0）或（（year MOD 4 = 0），而不是（年MOD 100 = 0））

Answer 5

有兩種簡單的解決方案：

5546>>m&1|30^(m==2)*2+(m==2&&y%4==0))) 

或

(62648012>>m*2&3)+28+(m==2&&y%4==0))) 

其中m是月和y的數量是那一年。

這個解決方案下面是一樣的數組，但是數組是用幻數掩蓋的。

Answer 6

要獲得當月的天數

Dim CurrentMonthDays As Int16 = DateTime.DaysInMonth(DateTime.Now.Year,DateTime.Now.Month)