方法一：//最有含量的一种

intdays=System.Threading.Thread.CurrentThread.CurrentUICulture.Calendar.GetDaysInMonth(DateTime.Now.Year,DateTime.Now.Month);方法二：//最奇怪的一种

DateTimedtNow=DateTime.Today;intdays=dtNow.AddDays(1-dtNow.Day).AddMonths(1).AddDays(-1).Day;方法三：//最常规的一种

DateTimedtNow=DateTime.Now;intdays=DateTime.DaysInMonth(dtNow.Year,dtNow.Month);