获取DateTime对象的Date部分对我来说没有效果，因为我在客户端工作，返回的web服务值有一些空日期。结果，它试图获取空值的Date部分，并抛出运行时异常。下面是我解决问题的方法:

string dt = employer.BirthDay.ToString();
if(dt == ""){ dt = "N/A";}
else dt = dt.Substring(0,10);

将DateTime值作为字符串转换为字符串变量。 检查它是否为空。如果为空，分配一个字符串变量。 如果不为空，则获取字符串DateTime值的前10个字符并将其分配给字符串变量。

我分享这个是为了将来参考。

我写了一个DateOnly结构。它在皮肤下使用一个DateTime，但没有时间部分被公开:

using System;

public struct DateOnly : IComparable, IFormattable, IComparable<DateOnly>, IEquatable<DateOnly>
{

    private DateTime _dateValue;

    public int CompareTo(object obj)
    {
        if (obj == null)
        {
            return 1;
        }

        DateOnly otherDateOnly = (DateOnly)obj;
        if (otherDateOnly != null)
        {
            return ToDateTime().CompareTo(otherDateOnly.ToDateTime());
        }
        else
        {
            throw new ArgumentException("Object is not a DateOnly");
        }
    }

    int IComparable<DateOnly>.CompareTo(DateOnly other)
    {
        return this.CompareToOfT(other);
    }
    public int CompareToOfT(DateOnly other)
    {
        // If other is not a valid object reference, this instance is greater.
        if (other == new DateOnly())
        {
            return 1;
        }
        return this.ToDateTime().CompareTo(other.ToDateTime());
    }

    bool IEquatable<DateOnly>.Equals(DateOnly other)
    {
        return this.EqualsOfT(other);
    }
    public bool EqualsOfT(DateOnly other)
    {
        if (other == new DateOnly())
        {
            return false;
        }

        if (this.Year == other.Year && this.Month == other.Month && this.Day == other.Day)
        {
            return true;
        }
        else
        {
            return false;
        }
    }

    public static DateOnly Now()
    {
        return new DateOnly(DateTime.Now.Year, DateTime.Now.Month, DateTime.Now.Day);
    }

    public static bool TryParse(string s, ref DateOnly result)
    {
        DateTime dateValue = default(DateTime);
        if (DateTime.TryParse(s, out dateValue))
        {
            result = new DateOnly(dateValue.Year, dateValue.Month, dateValue.Day);
            return true;
        }
        else
        {
            return false;
        }
    }

    public static DateOnly Parse(string s)
    {
        DateTime dateValue = default(DateTime);
        dateValue = DateTime.Parse(s);
        return new DateOnly(dateValue.Year, dateValue.Month, dateValue.Day);
    }

    public static DateOnly ParseExact(string s, string format)
    {
        CultureInfo provider = CultureInfo.InvariantCulture;
        DateTime dateValue = default(DateTime);
        dateValue = DateTime.ParseExact(s, format, provider);
        return new DateOnly(dateValue.Year, dateValue.Month, dateValue.Day);
    }

    public DateOnly(int yearValue, int monthValue, int dayValue) : this()
    {
        Year = yearValue;
        Month = monthValue;
        Day = dayValue;
    }

    public DateOnly AddDays(double value)
    {
        DateTime d = new DateTime(this.Year, this.Month, this.Day);
        d = d.AddDays(value);
        return new DateOnly(d.Year, d.Month, d.Day);
    }

    public DateOnly AddMonths(int months)
    {
        DateTime d = new DateTime(this.Year, this.Month, this.Day);
        d = d.AddMonths(months);
        return new DateOnly(d.Year, d.Month, d.Day);
    }

    public DateOnly AddYears(int years)
    {
        DateTime d = new DateTime(this.Year, this.Month, this.Day);
        d = d.AddYears(years);
        return new DateOnly(d.Year, d.Month, d.Day);
    }

    public DayOfWeek DayOfWeek
    {
        get
        {
            return _dateValue.DayOfWeek;
        }
    }

    public DateTime ToDateTime()
    {
        return _dateValue;
    }

    public int Year
    {
        get
        {
            return _dateValue.Year;
        }
        set
        {
            _dateValue = new DateTime(value, Month, Day);
        }
    }

    public int Month
    {
        get
        {
            return _dateValue.Month;
        }
        set
        {
            _dateValue = new DateTime(Year, value, Day);
        }
    }

    public int Day
    {
        get
        {
            return _dateValue.Day;
        }
        set
        {
            _dateValue = new DateTime(Year, Month, value);
        }
    }

    public static bool operator == (DateOnly aDateOnly1, DateOnly aDateOnly2)
    {
        return (aDateOnly1.ToDateTime() == aDateOnly2.ToDateTime());
    }

    public static bool operator != (DateOnly aDateOnly1, DateOnly aDateOnly2)
    {
        return (aDateOnly1.ToDateTime() != aDateOnly2.ToDateTime());
    }

    public static bool operator > (DateOnly aDateOnly1, DateOnly aDateOnly2)
    {
        return (aDateOnly1.ToDateTime() > aDateOnly2.ToDateTime());
    }

    public static bool operator < (DateOnly aDateOnly1, DateOnly aDateOnly2)
    {
        return (aDateOnly1.ToDateTime() < aDateOnly2.ToDateTime());
    }

    public static bool operator >= (DateOnly aDateOnly1, DateOnly aDateOnly2)
    {
        return (aDateOnly1.ToDateTime() >= aDateOnly2.ToDateTime());
    }

    public static bool operator <= (DateOnly aDateOnly1, DateOnly aDateOnly2)
    {
        return (aDateOnly1.ToDateTime() <= aDateOnly2.ToDateTime());
    }

    public static TimeSpan operator - (DateOnly aDateOnly1, DateOnly aDateOnly2)
    {
        return (aDateOnly1.ToDateTime() - aDateOnly2.ToDateTime());
    }


    public override string ToString()
    {
        return _dateValue.ToShortDateString();
    }

    public string ToString(string format)
    {
        return _dateValue.ToString(format);
    }

    public string ToString(string fmt, IFormatProvider provider)
    {
        return string.Format("{0:" + fmt + "}", _dateValue);
    }

    public string ToShortDateString()
    {
        return _dateValue.ToShortDateString();
    }

    public string ToDbFormat()
    {
        return string.Format("{0:yyyy-MM-dd}", _dateValue);
    }
}

这是从VB转换过来的。NET，所以抱歉，如果一些转换不是100%

使用Date属性:

var dateAndTime = DateTime.Now;
var date = dateAndTime.Date;

date变量将包含日期，时间部分将是00:00:00。

将Date属性添加到DateTime变量

var dateTime = DateTime.Now
var onlyDate = dateTime.Date

或者您也可以使用DataType注释。

[DataType(DataType.Date)]
public DateTime dateTime {get; set;}

DataType注释位于System.ComponentModel.DataAnnotations命名空间内。

我知道这是一个有很多答案的老帖子，但我还没有见过这种删除时间部分的方法。假设您有一个名为myDate的DateTime变量，其中日期和时间部分。你可以从它创建一个新的DateTime对象，没有时间部分，使用这个构造函数:

public DateTime(int year, int month, int day);

是这样的:

myDate = new DateTime(myDate.Year, myDate.Month, myDate.Day);

通过这种方式，您可以基于旧的DateTime对象创建一个新的DateTime对象，其中00:00:00作为时间部分。

这可以简单地这样做:

var dateOnly = new DateTime(dateTime.Year, dateTime.Month, dateTime.Day)