/// <summary>
/// Gets first day of quarter. <br />
/// 获取一个季度的第一天。
/// </summary>
/// <param name="ld"></param>
/// <returns></returns>
public static LocalDate FirstDayOfQuarter(this LocalDate ld)
{
var currentQuarter = (ld.Month - 1) / 3 + 1;
var firstDay = new LocalDate(ld.Year, 3 * currentQuarter - 2, 1);
return(ld.SetDate(firstDay.Year, firstDay.Month, firstDay.Day));
}
/// <summary>
/// Gets last day of quarter.<br />
/// 获取一个季度的最后一天。
/// </summary>
/// <param name="ld"></param>
/// <returns></returns>
public static LocalDate LastDayOfQuarter(this LocalDate ld)
{
var currentQuarter = (ld.Month - 1) / 3 + 1;
var firstDay = ld.SetDate(ld.Year, 3 * currentQuarter - 2, 1);
return(firstDay.SetMonth(firstDay.Month + 2).LastDayOfMonth());
}
/// <summary>
/// Gets previous month.<br />
/// 上一个月。
/// </summary>
/// <param name="ld"></param>
/// <returns></returns>
public static LocalDate PreviousMonth(this LocalDate ld)
{
var year = ld.Month == 1 ? ld.Year - 1 : ld.Year;
var month = ld.Month == 1 ? 12 : ld.Month - 1;
var firstDayOfPreviousMonth = ld.SetDate(year, month, 1);
var lastDayOfPreviousMonth = firstDayOfPreviousMonth.LastDayOfMonth().Day;
var day = ld.Day > lastDayOfPreviousMonth ? lastDayOfPreviousMonth : ld.Day;
return(firstDayOfPreviousMonth.SetDay(day));
}
/// <summary> /// Gets first day of year. <br /> /// 获取一年的第一天。 /// </summary> /// <param name="ld"></param> /// <returns></returns> public static LocalDate FirstDayOfYear(this LocalDate ld) => ld.SetDate(ld.Year, 1, 1);
/// <summary> /// Gets last day of year.<br /> /// 获取一年的最后一天。 /// </summary> /// <param name="ld"></param> /// <returns></returns> public static LocalDate LastDayOfYear(this LocalDate ld) => ld.SetDate(ld.Year, 12, 31);