C#计算工龄/年龄

/// <summary>
/// 计算工龄
/// </summary>
/// <param name="time1"></param>
/// <param name="time2"></param>
/// <returns></returns>
public static double CalcYear(DateTime time1, DateTime time2)
{
	var year = time2.Year - time1.Year;
	if (time2.Month < time1.Month || (time2.Month == time1.Month && time2.Day < time1.Day))
	{
		year = year - 1;
	}

	var nearYear = new DateTime(time2.Year - 1, time1.Month, time1.Day);
	if (time2.Month > time1.Month || (time2.Month == time1.Month && time2.Day >= time1.Day))
	{
		nearYear = new DateTime(time2.Year, time1.Month, time1.Day);
	}
	int days = (nearYear.AddYears(1) - nearYear).Days;
	var dotValue = Math.Floor((time2 - nearYear).TotalDays * 100 / days) / 100;
	return year + dotValue;
}

List<string[]> testGroups = new List<string[]>()
{
	new string[]{ "2022-02-01", "2023-01-01" },
	new string[]{ "2022-02-01", "2023-02-03" },
	new string[]{ "2022-02-01", "2024-01-31" },
	new string[]{ "2022-02-01", "2024-02-02" },
	new string[]{ "2022-02-01", "2024-02-01" }
};
foreach (var g in testGroups)
{
	DateTime timeStart = DateTime.Parse(g[0]);
	DateTime timeEnd = DateTime.Parse(g[1]);
	var value = Tools.CalcYear(timeStart, timeEnd);
	Console.WriteLine($"{timeStart.ToString("yyyy-MM-dd")} 至 {timeEnd.ToString("yyyy-MM-dd")} 计算值：{value}");
}

/// <summary>
/// 计算年龄
/// </summary>
/// <param name="brithday"></param>
/// <returns></returns>
public static int CalcAge(DateTime brithday)
{
	var today = DateTime.Today;
	var year = DateTime.Today.Year - brithday.Year;
	if (today.Month < brithday.Month || (today.Month == brithday.Month && today.Day < brithday.Day))
	{
		year = year - 1;
	}
	return year;
}