你可以简单地使用Split

 new TimeSpan(new DateTime(1970, 1, 1).Ticks).TotalSeconds.ToString().Split('.')[0]

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);

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

不那么明显，但快了2倍多:

// 10000000 runs

DateTime d = DateTime.Now;

// 484,375ms
d = new DateTime((d.Ticks / TimeSpan.TicksPerSecond) * TimeSpan.TicksPerSecond);

// 1296,875ms
d = d.AddMilliseconds(-d.Millisecond);

我知道答案很晚了，但是摆脱毫秒的最好方法是

var currentDateTime = DateTime.Now.ToString("s");

尝试打印变量的值，它将显示日期时间，没有毫秒。

一种简单的阅读方法是……

//Remove milliseconds
DateTime date = DateTime.Now;
date = DateTime.ParseExact(date.ToString("yyyy-MM-dd HH:mm:ss"), "yyyy-MM-dd HH:mm:ss", null);

和更多的……

//Remove seconds
DateTime date = DateTime.Now;
date = DateTime.ParseExact(date.ToString("yyyy-MM-dd HH:mm"), "yyyy-MM-dd HH:mm", null);

//Remove minutes
DateTime date = DateTime.Now;
date = DateTime.ParseExact(date.ToString("yyyy-MM-dd HH"), "yyyy-MM-dd HH", null);

//and go on...

我知道这很容易理解，但是它缺乏性能。