VS.NET获取某年某月的天数

public static int getDaysOfMonth(int theYear, int theMonth)//獲取某年某月的天數
        {
            int days = 0;
            switch (theMonth)
            {
                case 1:
                    days = 31;
                    break;
                case 2:
                    if (DateTime.IsLeapYear(theYear))
                    {
                        //闰年二月为29天
                        days = 29;
                    }
                    else
                    {
                        //不是闰年，二月为28天
                        days = 28;
                    }
                    break;
                case 3:
                    days = 31;
                    break;
                case 4:
                    days = 30;
                    break;
                case 5:
                    days = 31;
                    break;
                case 6:
                    days = 30;
                    break;
                case 7:
                    days = 31;
                    break;
                case 8:
                    days = 31;
                    break;
                case 9:
                    days = 30;
                    break;
                case 10:
                    days = 31;
                    break;
                case 11:
                    days = 30;
                    break;
                case 12:
                    days = 31;
                    break;
            }

            return days;
        }