如何在c#中找到一个月的最后一天?
例如,如果我有日期03/08/1980,我如何得到第8个月的最后一天(在本例中是31)?
如何在c#中找到一个月的最后一天?
例如,如果我有日期03/08/1980,我如何得到第8个月的最后一天(在本例中是31)?
当前回答
从DateTimePicker:
第一次约会:
DateTime first_date = new DateTime(DateTimePicker.Value.Year, DateTimePicker.Value.Month, 1);
最后的日期:
DateTime last_date = new DateTime(DateTimePicker.Value.Year, DateTimePicker.Value.Month, DateTime.DaysInMonth(DateTimePicker.Value.Year, DateTimePicker.Value.Month));
其他回答
您可以按以下方式扩展DateTime;
public static class DateTimeMethods
{
public static DateTime StartOfMonth(this DateTime date)
{
return new DateTime(date.Year, date.Month, 1, 0, 0, 0);
}
public static DateTime EndOfMonth(this DateTime date)
{
return date.StartOfMonth().AddMonths(1).AddSeconds(-1);
}
}
像这样使用它;
DateTime today = DateTime.Now;
DateTime startOfMonth = today.StartOfMonth();
DateTime endOfMonth = today.EndOfMonth();
// Use any date you want, for the purpose of this example we use 1980-08-03.
var myDate = new DateTime(1980,8,3);
var lastDayOfMonth = new DateTime(myDate.Year, myDate.Month, DateTime.DaysInMonth(myDate.Year, myDate.Month));
这个月的最后一天你会得到这样的结果,返回31:
DateTime.DaysInMonth(1980, 08);
要获得特定日历中一个月的最后一天-并在扩展方法中-:
public static int DaysInMonthBy(this DateTime src, Calendar calendar)
{
var year = calendar.GetYear(src); // year of src in your calendar
var month = calendar.GetMonth(src); // month of src in your calendar
var lastDay = calendar.GetDaysInMonth(year, month); // days in month means last day of that month in your calendar
return lastDay;
}
例如2021年5月7日
DateTime.Now.Day;
结果:5
DateTime.Now.AddMonths(+1).AddDays(-DateTime.Now.Day).ToString(“yyyy-MM-dd”);
结果:2021/07/31