关于糖尿病反应。这对我来说是可行的，除了我必须在乘法之前使用Floor来去除除法的小数部分。所以,

d = new DateTime((d.Ticks / TimeSpan.TicksPerSecond) * TimeSpan.TicksPerSecond);

就变成了

d = new DateTime(Math.Floor(d.Ticks / TimeSpan.TicksPerSecond) * TimeSpan.TicksPerSecond);

我本希望两个Long值的除法结果是Long，从而去掉小数部分，但它将其解析为Double，在乘法之后保留完全相同的值。

埃普西

DateTime d = DateTime.Now;
d = d.AddMilliseconds(-d.Millisecond);

var date = DateTime.Now;

date = new DateTime(date.Year, date.Month, date.Day, date.Hour, date.Minute, date.Second, date.Kind);

2上述解决方案的扩展方法

    public static bool LiesAfterIgnoringMilliseconds(this DateTime theDate, DateTime compareDate, DateTimeKind kind)
    {
        DateTime thisDate = new DateTime(theDate.Year, theDate.Month, theDate.Day, theDate.Hour, theDate.Minute, theDate.Second, kind);
        compareDate = new DateTime(compareDate.Year, compareDate.Month, compareDate.Day, compareDate.Hour, compareDate.Minute, compareDate.Second, kind);

        return thisDate > compareDate;
    }


    public static bool LiesAfterOrEqualsIgnoringMilliseconds(this DateTime theDate, DateTime compareDate, DateTimeKind kind)
    {
        DateTime thisDate = new DateTime(theDate.Year, theDate.Month, theDate.Day, theDate.Hour, theDate.Minute, theDate.Second, kind);
        compareDate = new DateTime(compareDate.Year, compareDate.Month, compareDate.Day, compareDate.Hour, compareDate.Minute, compareDate.Second, kind);

        return thisDate >= compareDate;
    }

用法:

bool liesAfter = myObject.DateProperty.LiesAfterOrEqualsIgnoringMilliseconds(startDateTime, DateTimeKind.Utc);

在我的情况下，我的目标是从datetimePicker工具保存TimeSpan，而不节省秒和毫秒，这里是解决方案。

首先转换datetimePicker。值转换为你想要的格式，我的格式是“HH:mm”，然后将其转换回TimeSpan格式。

var datetime = datetimepicker1.Value.ToString("HH:mm");
TimeSpan timeSpan = Convert.ToDateTime(datetime).TimeOfDay;

新方法

String Date = DateTime.Today.ToString("dd-MMM-yyyy"); 

//定义字符串传递参数dd-mm -yyyy返回24-feb-2016

或显示在文本框上

txtDate.Text = DateTime.Today.ToString("dd-MMM-yyyy");

//加载pagonload