如何在C#.net中选择月份的最后一个日期？

Question

我正在使用下拉列表来选择.aspx页面中的月份.我必须在.aspx.cs页面中获取所选月份的最后日期.(有些月份有30天,有些月份有31天)

我怎样才能做到这一点？

Answer 1

不需要自定义计算.

使用该System.DateTime.DaysInMonth(yearNum, monthNum)方法查找任何给定月份(也是最后一天)的天数.

它很简单:

//Get days in month 2 (Feb) of year 2011. Returns 28.
int daysInFeb2011 = System.DateTime.DaysInMonth(2011, 2); 

MSDN文档提供了更全面和描述性的示例:

        const int July = 7;
        const int Feb = 2;

        // daysInJuly gets 31.
        int daysInJuly = System.DateTime.DaysInMonth(2001, July);

        // daysInFeb gets 28 because the year 1998 was not a leap year.
        int daysInFeb = System.DateTime.DaysInMonth(1998, Feb);

        // daysInFebLeap gets 29 because the year 1996 was a leap year.
        int daysInFebLeap = System.DateTime.DaysInMonth(1996, Feb);