您将如何使用出生日期(考虑闰年)计算 C# 中的年龄

年龄非常棘手。这是我使用的结构的相关摘录。

public struct Age
{
    private readonly Int32 _years;
    private readonly Int32 _months;
    private readonly Int32 _days;
    private readonly Int32 _totalDays;
    /// <summary>
    /// Initializes a new instance of <see cref="Age"/>.
    /// </summary>
    /// <param name="start">The date and time when the age started.</param>
    /// <param name="end">The date and time when the age ended.</param>
    /// <remarks>This </remarks>
    public Age(DateTime start, DateTime end)
        : this(start, end, CultureInfo.CurrentCulture.Calendar)
    {
    }
    /// <summary>
    /// Initializes a new instance of <see cref="Age"/>.
    /// </summary>
    /// <param name="start">The date and time when the age started.</param>
    /// <param name="end">The date and time when the age ended.</param>
    /// <param name="calendar">Calendar used to calculate age.</param>
    public Age(DateTime start, DateTime end, Calendar calendar)
    {
        if (start > end) throw new ArgumentException("The starting date cannot be later than the end date.");
        var startDate = start.Date;
        var endDate = end.Date;
        _years = _months = _days = 0;
        _days += calendar.GetDayOfMonth(endDate) - calendar.GetDayOfMonth(startDate);
        if (_days < 0)
        {
            _days += calendar.GetDaysInMonth(calendar.GetYear(startDate), calendar.GetMonth(startDate));
            _months--;
        }
        _months += calendar.GetMonth(endDate) - calendar.GetMonth(startDate);
        if (_months < 0)
        {
            _months += calendar.GetMonthsInYear(calendar.GetYear(startDate));
            _years--;
        }
        _years += calendar.GetYear(endDate) - calendar.GetYear(startDate);
        var ts = endDate.Subtract(startDate);
        _totalDays = (Int32)ts.TotalDays;
    }
    /// <summary>
    /// Gets the number of whole years something has aged.
    /// </summary>
    public Int32 Years
    {
        get { return _years; }
    }
    /// <summary>
    /// Gets the number of whole months something has aged past the value of <see cref="Years"/>.
    /// </summary>
    public Int32 Months
    {
        get { return _months; }
    }
    /// <summary>
    /// Gets the age as an expression of whole months.
    /// </summary>
    public Int32 TotalMonths
    {
        get { return _years * 12 + _months; }
    }
    /// <summary>
    /// Gets the number of whole weeks something has aged past the value of <see cref="Years"/> and <see cref="Months"/>.
    /// </summary>
    public Int32 Days
    {
        get { return _days; }
    }
    /// <summary>
    /// Gets the total number of days that have elapsed since the start and end dates.
    /// </summary>
    public Int32 TotalDays
    {
        get { return _totalDays; }
    }
    /// <summary>
    /// Gets the number of whole weeks something has aged past the value of <see cref="Years"/> and <see cref="Months"/>.
    /// </summary>
    public Int32 Weeks
    {
        get { return (Int32) Math.Floor((Decimal) _days/7); }
    }
    /// <summary>
    /// Gets the age as an expression of whole weeks.
    /// </summary>
    public Int32 TotalWeeks
    {
        get { return (Int32) Math.Floor((Decimal) _totalDays/7); }
    }
}

下面是通过的示例单元测试：

    [Test]
    public void Should_be_exactly_20_years_old()
    {
        var now = DateTime.Now;
        var age = new Age(now.AddYears(-20), now);
        Assert.That(age, Has.Property("Years").EqualTo(20)
            .And.Property("Months").EqualTo(0)
            .And.Property("Days").EqualTo(0));
    }

用途

Timespan interval = DateTime.Now - DateOfBirth;

然后使用

interval.Days
interval.TotalDays;
interval.Hours;
interval.TotalHours;
interval.Minutes;
interval.TotalMinutes;
interval.Seconds;
interval.TotalSeconds;
interval.Milliseconds;
interval.TotalMilliseconds;
interval.Ticks;

以获得所需的结果。

static int AgeInYears(DateTime birthday, DateTime today)
{
    return ((today.Year - birthday.Year) * 372 + (today.Month - birthday.Month) * 31 + (today.Day - birthday.Day)) / 372;
}

编写这个小函数，以获得当前年份和出生年份之间的闰年天数，并将返回的天数添加到您的年龄部分：

 private static int NumberOfLeapYears(int startYear, int endYear)
 {         
 int counter = 0;
 for (int year = startYear; year <= endYear; year++)
 counter += DateTime.IsLeapYear(year) ? 1 : 0;
 return counter;
 } 

检查此代码：

{                                                    
    dif = int(datediff("D", Convert.ToDateTime("01/" + Q101m.text + "/" + Q101y.Text), (Convert.ToDateTime(Vdate.text)))/365.25)
    //If dif < 15 Or dif > 49 
    {
           MessageBox.Show("xxxxxxx");
           Q101m.Focus();
    }
}

我在 DateTime 类中创建了一个解决方案作为扩展方法，该解决方案是从@HackedByChinese"派生"出来的：

    /// <summary>
    /// Calculate age in years relative to months and days, for example Peters age is 25 years 2 months and 10 days
    /// </summary>
    /// <param name="startDate">The date when the age started</param>
    /// <param name="endDate">The date when the age ended</param>
    /// <param name="calendar">Calendar used to calculate age</param>
    /// <param name="years">Return number of years, with considering months and days</param>
    /// <param name="months">Return calculated months</param>
    /// <param name="days">Return calculated days</param>
    public static bool GetAge(this DateTime startDate, DateTime endDate, Calendar calendar, out int years, out int months, out int days)
    {
        if (startDate > endDate)
        {
            years = months = days = -1;
            return false;
        }
        years = months = days = 0;
        days += calendar.GetDayOfMonth(endDate) - calendar.GetDayOfMonth(startDate);
        // When negative select days of last month
        if (days < 0)
        {
            days += calendar.GetDaysInMonth(calendar.GetYear(startDate), calendar.GetMonth(startDate));
            months--;
        }
        months += calendar.GetMonth(endDate) - calendar.GetMonth(startDate);
        // when negative select month of last year
        if (months < 0)
        {
            months += calendar.GetMonthsInYear(calendar.GetYear(startDate));
            years--;
        }
        years += calendar.GetYear(endDate) - calendar.GetYear(startDate);
        return true;
    }

但我认识到结果天数可能与其他计算器略有不同。