计算一个月的天数

Question

有没有计算一个月天数的方法？

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)

信用转到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

您当然可以更改输出日期的方式，以便将其格式化为您的意愿。

Answer 4

获取当月的天数

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

Answer 5

使用数组：[31,28,31,30,31,30,31,31,30,31,30,31] 如果（年份mod 400 = 0）或（（年份mod 4 = 0）而不是（年份mod 100 = 0），则添加1到2月

Answer 6

您有两个简单的解决方案：

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是月份，y是年份。

这个解决方案在下面是一个数组，但数组是用魔术数字掩盖的。