Struct XDate

This struct encapsulates a date and time value, and handles associated calculations and conversions between various formats.

Implements

IComparable

Inherited Members

Object.Equals(Object, Object)

Object.GetType()

Object.ReferenceEquals(Object, Object)

Namespace: ZedGraph

Assembly: ZedGraph.dll

Syntax

public struct XDate : IComparable

Remarks

This format stored as a double value representing days since a reference date (XL date 0.0 is December 30, 1899 at 00:00 hrs). Negative values are permissible, and the range of valid dates is from noon on January 1st, 4713 B.C. forward. Internally, the date calculations are done using Astronomical Julian Day numbers. The Astronomical Julian Day number is defined as the number of days since noon on January 1st, 4713 B.C. (also referred to as 12:00 on January 1, -4712). NOTE: MS Excel actually has an error in the Serial Date calculations because it errantly assumes 1900 is a leap year. The XDate calculations do not have this same error. Therefore, XDate and Excel Date Serial values are 1 day different up until the date value of 60 (in Excel, this is February 29th, 1900, and in XDate, this is February 28th, 1900). At a value of 61 (March 1st, 1900) or greater, they agree with eachother.

Constructors

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XDate(DateTime)

Construct a date class from a DateTime struct.

Declaration

public XDate(DateTime dateTime)

Parameters

Type	Name	Description
DateTime	dateTime	A DateTime struct containing the initial date information.

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XDate(Double)

Construct a date class from an XL date value.

Declaration

public XDate(double xlDate)

Parameters

Type	Name	Description
Double	xlDate	An XL Date value in floating point double format

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XDate(Int32, Int32, Int32)

Construct a date class from a calendar date (year, month, day). Assumes the time of day is 00:00 hrs

Declaration

public XDate(int year, int month, int day)

Parameters

Type	Name	Description
Int32	year	An integer value for the year, e.g., 1995.
Int32	month	An integer value for the month of the year, e.g., 8 for August. It is permissible to have months outside of the 1-12 range, which will rollover to the previous or next year.
Int32	day	An integer value for the day of the month, e.g., 23. It is permissible to have day numbers outside of the 1-31 range, which will rollover to the previous or next month and year.

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XDate(Int32, Int32, Int32, Int32, Int32, Double)

Construct a date class from a calendar date and time (year, month, day, hour, minute, second), where seconds is a Double value (allowing fractional seconds).

Declaration

public XDate(int year, int month, int day, int hour, int minute, double second)

Parameters

Type	Name	Description
Int32	year	An integer value for the year, e.g., 1995.
Int32	month	An integer value for the month of the year, e.g., 8 for August. It is permissible to have months outside of the 1-12 range, which will rollover to the previous or next year.
Int32	day	An integer value for the day of the month, e.g., 23. It is permissible to have day numbers outside of the 1-31 range, which will rollover to the previous or next month and year.
Int32	hour	An integer value for the hour of the day, e.g. 15. It is permissible to have hour values outside the 0-23 range, which will rollover to the previous or next day.
Int32	minute	An integer value for the minute, e.g. 45. It is permissible to have hour values outside the 0-59 range, which will rollover to the previous or next hour.
Double	second	A double value for the second, e.g. 35.75. It is permissible to have second values outside the 0-59 range, which will rollover to the previous or next minute.

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XDate(Int32, Int32, Int32, Int32, Int32, Int32)

Construct a date class from a calendar date and time (year, month, day, hour, minute, second).

Declaration

public XDate(int year, int month, int day, int hour, int minute, int second)

Parameters

Type	Name	Description
Int32	year	An integer value for the year, e.g., 1995.
Int32	month	An integer value for the month of the year, e.g., 8 for August. It is permissible to have months outside of the 1-12 range, which will rollover to the previous or next year.
Int32	day	An integer value for the day of the month, e.g., 23. It is permissible to have day numbers outside of the 1-31 range, which will rollover to the previous or next month and year.
Int32	hour	An integer value for the hour of the day, e.g. 15. It is permissible to have hour values outside the 0-23 range, which will rollover to the previous or next day.
Int32	minute	An integer value for the minute, e.g. 45. It is permissible to have hour values outside the 0-59 range, which will rollover to the previous or next hour.
Int32	second	An integer value for the second, e.g. 35. It is permissible to have second values outside the 0-59 range, which will rollover to the previous or next minute.

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XDate(Int32, Int32, Int32, Int32, Int32, Int32, Int32)

Construct a date class from a calendar date and time (year, month, day, hour, minute, second, millisecond).

Declaration

public XDate(int year, int month, int day, int hour, int minute, int second, int millisecond)

Parameters

Type	Name	Description
Int32	year	An integer value for the year, e.g., 1995.
Int32	month	An integer value for the month of the year, e.g., 8 for August. It is permissible to have months outside of the 1-12 range, which will rollover to the previous or next year.
Int32	day	An integer value for the day of the month, e.g., 23. It is permissible to have day numbers outside of the 1-31 range, which will rollover to the previous or next month and year.
Int32	hour	An integer value for the hour of the day, e.g. 15. It is permissible to have hour values outside the 0-23 range, which will rollover to the previous or next day.
Int32	minute	An integer value for the minute, e.g. 45. It is permissible to have hour values outside the 0-59 range, which will rollover to the previous or next hour.
Int32	second	An integer value for the second, e.g. 35. It is permissible to have second values outside the 0-59 range, which will rollover to the previous or next minute.
Int32	millisecond	An integer value for the millisecond, e.g. 632. It is permissible to have millisecond values outside the 0-999 range, which will rollover to the previous or next second.

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XDate(XDate)

The Copy Constructor

Declaration

public XDate(XDate rhs)

Parameters

Type	Name	Description
XDate	rhs	The GraphPane object from which to copy

Fields

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DefaultFormatStr

The default format string to be used in ToString() when no format is provided

Declaration

public const string DefaultFormatStr = "g"

Field Value

Type	Description
String

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HoursPerDay

The number of hours in a day

Declaration

public const double HoursPerDay = 24

Field Value

Type	Description
Double

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JulDayMax

The maximum valid Julian Day, which corresponds to December 31st, 9999 A.D.

Declaration

public const double JulDayMax = 5373483.5

Field Value

Type	Description
Double

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JulDayMin

The minimum valid Julian Day, which corresponds to January 1st, 4713 B.C.

Declaration

public const double JulDayMin = 0

Field Value

Type	Description
Double

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MillisecondsPerDay

The number of milliseconds in a day

Declaration

public const double MillisecondsPerDay = 86400000

Field Value

Type	Description
Double

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MillisecondsPerSecond

The number of milliseconds in a second

Declaration

public const double MillisecondsPerSecond = 1000

Field Value

Type	Description
Double

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MinutesPerDay

The number of minutes in a day

Declaration

public const double MinutesPerDay = 1440

Field Value

Type	Description
Double

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MinutesPerHour

The number of minutes in an hour

Declaration

public const double MinutesPerHour = 60

Field Value

Type	Description
Double

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MonthsPerYear

The number of months in a year

Declaration

public const double MonthsPerYear = 12

Field Value

Type	Description
Double

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SecondsPerDay

The number of seconds in a day

Declaration

public const double SecondsPerDay = 86400

Field Value

Type	Description
Double

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SecondsPerMinute

The number of seconds in a minute

Declaration

public const double SecondsPerMinute = 60

Field Value

Type	Description
Double

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XLDay1

The Astronomical Julian Day number that corresponds to XL Date 0.0

Declaration

public const double XLDay1 = 2415018.5

Field Value

Type	Description
Double

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XLDayMax

The maximum valid Excel Day, which corresponds to December 31st, 9999 A.D.

Declaration

public const double XLDayMax = 2958465

Field Value

Type	Description
Double

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XLDayMin

The minimum valid Excel Day, which corresponds to January 1st, 4713 B.C.

Declaration

public const double XLDayMin = -2415018.5

Field Value

Type	Description
Double

Properties

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DateTime

Gets or sets the date value for this item in .Net DateTime format.

Declaration

public DateTime DateTime { get; set; }

Property Value

Type	Description
DateTime

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DecimalYear

Gets or sets the decimal year number (i.e., 1997.345) corresponding to this item.

Declaration

public double DecimalYear { get; set; }

Property Value

Type	Description
Double

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IsValidDate

Returns true if this XDate struct is in the valid date range

Declaration

public bool IsValidDate { get; }

Property Value

Type	Description
Boolean

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JulianDay

Gets or sets the date value for this item in Julain day format. This is the Astronomical Julian Day number, so a value of 0.0 corresponds to noon GMT on January 1st, -4712. Thus, Julian Day number 2,400,000.0 corresponds to noon GMT on November 16, 1858.

Declaration

public double JulianDay { get; set; }

Property Value

Type	Description
Double

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XLDate

Gets or sets the date value for this item in MS Excel format.

Declaration

public double XLDate { get; set; }

Property Value

Type	Description
Double

Methods

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AddDays(Double)

Add the specified number of days (can be fractional) to the current XDate instance.

Declaration

public void AddDays(double dDays)

Parameters

Type	Name	Description
Double	dDays	The incremental number of days (negative or positive) in floating point double format.

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AddHours(Double)

Add the specified number of hours (can be fractional) to the current XDate instance.

Declaration

public void AddHours(double dHours)

Parameters

Type	Name	Description
Double	dHours	The incremental number of hours (negative or positive) in floating point double format.

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AddMilliseconds(Double)

Add the specified number of milliseconds (can be fractional) to the current XDate instance.

Declaration

public void AddMilliseconds(double dMilliseconds)

Parameters

Type	Name	Description
Double	dMilliseconds	The incremental number of milliseconds (negative or positive) in floating point double format.

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AddMinutes(Double)

Add the specified number of minutes (can be fractional) to the current XDate instance.

Declaration

public void AddMinutes(double dMinutes)

Parameters

Type	Name	Description
Double	dMinutes	The incremental number of minutes (negative or positive) in floating point double format.

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AddMonths(Double)

Add the specified number of Months (can be fractional) to the current XDate instance.

Declaration

public void AddMonths(double dMonths)

Parameters

Type	Name	Description
Double	dMonths	The incremental number of months (negative or positive) in floating point double format.

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AddSeconds(Double)

Add the specified number of seconds (can be fractional) to the current XDate instance.

Declaration

public void AddSeconds(double dSeconds)

Parameters

Type	Name	Description
Double	dSeconds	The incremental number of seconds (negative or positive) in floating point double format.

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AddYears(Double)

Add the specified number of years (can be fractional) to the current XDate instance.

Declaration

public void AddYears(double dYears)

Parameters

Type	Name	Description
Double	dYears	The incremental number of years (negative or positive) in floating point double format.

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CalendarDateToJulianDay(Int32, Int32, Int32, Int32, Int32, Int32)

Calculate an Astronomical Julian Day number from the specified Calendar date (year, month, day, hour, minute, second), first normalizing all input data values

Declaration

public static double CalendarDateToJulianDay(int year, int month, int day, int hour, int minute, int second)

Parameters

Type	Name	Description
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Int32	second	The integer second value (e.g., 42 for 42 seconds past the minute).

Returns

Type	Description
Double	The corresponding Astronomical Julian Day number, expressed in double floating point format

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CalendarDateToJulianDay(Int32, Int32, Int32, Int32, Int32, Int32, Int32)

Calculate an Astronomical Julian Day number from the specified Calendar date (year, month, day, hour, minute, second), first normalizing all input data values

Declaration

public static double CalendarDateToJulianDay(int year, int month, int day, int hour, int minute, int second, int millisecond)

Parameters

Type	Name	Description
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Int32	second	The integer second value (e.g., 42 for 42 seconds past the minute).
Int32	millisecond	The integer second value (e.g., 325 for 325 milliseconds past the minute).

Returns

Type	Description
Double	The corresponding Astronomical Julian Day number, expressed in double floating point format

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CalendarDateToXLDate(Int32, Int32, Int32, Int32, Int32, Double)

Calculate an XL Date from the specified Calendar date (year, month, day, hour, minute, second), first normalizing all input data values. The seconds value is a double type, allowing fractional seconds.

Declaration

public static double CalendarDateToXLDate(int year, int month, int day, int hour, int minute, double second)

Parameters

Type	Name	Description
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Double	second	The double second value (e.g., 42.3 for 42.3 seconds past the minute).

Returns

Type	Description
Double	The corresponding XL date, expressed in double floating point format

Remarks

The Calendar date is always based on the Gregorian Calendar. Note that the Gregorian calendar is really only valid from October 15, 1582 forward. The countries that adopted the Gregorian calendar first did so on October 4, 1582, so that the next day was October 15, 1582. Prior to that time the Julian Calendar was used. However, Prior to March 1, 4 AD the treatment of leap years was inconsistent, and prior to 45 BC the Julian Calendar did not exist. The XDate struct projects only Gregorian dates backwards and does not deal with Julian calendar dates at all. The ToString(Double, String) method will just append a "(BC)" notation to the end of any dates prior to 1 AD, since the DateTime struct throws an exception when formatting earlier dates.

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CalendarDateToXLDate(Int32, Int32, Int32, Int32, Int32, Int32)

Calculate an XL Date from the specified Calendar date (year, month, day, hour, minute, second), first normalizing all input data values.

Declaration

public static double CalendarDateToXLDate(int year, int month, int day, int hour, int minute, int second)

Parameters

Type	Name	Description
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Int32	second	The integer second value (e.g., 42 for 42 seconds past the minute).

Returns

Type	Description
Double	The corresponding XL date, expressed in double floating point format

Remarks

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CalendarDateToXLDate(Int32, Int32, Int32, Int32, Int32, Int32, Int32)

Calculate an XL Date from the specified Calendar date (year, month, day, hour, minute, second), first normalizing all input data values.

Declaration

public static double CalendarDateToXLDate(int year, int month, int day, int hour, int minute, int second, int millisecond)

Parameters

Type	Name	Description
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Int32	second	The integer second value (e.g., 42 for 42 seconds past the minute).
Int32	millisecond	The integer millisecond value (e.g., 374 for 374 milliseconds past the second).

Returns

Type	Description
Double	The corresponding XL date, expressed in double floating point format

Remarks

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CompareTo(Object)

Compares one XDate object to another.

Declaration

public int CompareTo(object target)

Parameters

Type	Name	Description
Object	target	The second XDate object to be compared.

Returns

Type	Description
Int32	zero if `target` is equal to the current instance, -1 if `target` is less than the current instance, and 1 if `target` is greater than the current instance.

Remarks

This method will throw an exception if target is not an XDate object.

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DateTimeToXLDate(DateTime)

Convert a .Net DateTime struct to an XL Format date

Declaration

public static double DateTimeToXLDate(DateTime dt)

Parameters

Type	Name	Description
DateTime	dt	The date value in the form of a .Net DateTime struct

Returns

Type	Description
Double	The corresponding XL Date, expressed in double floating point format

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DecimalYearToXLDate(Double)

Calculate a decimal year value (e.g., 1994.6523) corresponding to the specified XL date

Declaration

public static double DecimalYearToXLDate(double yearDec)

Parameters

Type	Name	Description
Double	yearDec	The decimal year value in floating point double format.

Returns

Type	Description
Double	The corresponding XL Date, expressed in double floating point format

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Equals(Object)

Tests whether obj is either an XDate structure or a double floating point value that is equal to the same date as this XDate struct instance.

Declaration

public override bool Equals(object obj)

Parameters

Type	Name	Description
Object	obj	The object to compare for equality with this XDate instance. This object should be either a type XDate or type double.

Returns

Type	Description
Boolean	Returns `true` if obj is the same date as this instance; otherwise, `false`

Overrides

ValueType.Equals(Object)

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GetDate(out Int32, out Int32, out Int32)

Get the calendar date (year, month, day) corresponding to this instance.

Declaration

public void GetDate(out int year, out int month, out int day)

Parameters

Type	Name	Description
Int32	year	An integer value for the year, e.g., 1995.
Int32	month	An integer value for the month of the year, e.g., 8 for August.
Int32	day	An integer value for the day of the month, e.g., 23.

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GetDate(out Int32, out Int32, out Int32, out Int32, out Int32, out Int32)

Get the calendar date (year, month, day, hour, minute, second) corresponding to this instance.

Declaration

public void GetDate(out int year, out int month, out int day, out int hour, out int minute, out int second)

Parameters

Type	Name	Description
Int32	year	An integer value for the year, e.g., 1995.
Int32	month	An integer value for the month of the year, e.g., 8 for August.
Int32	day	An integer value for the day of the month, e.g., 23.
Int32	hour	An integer value for the hour of the day, e.g. 15.
Int32	minute	An integer value for the minute, e.g. 45.
Int32	second	An integer value for the second, e.g. 35.

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GetDayOfYear()

Get the day of year value (241.345 means the 241st day of the year) corresponding to this instance.

Declaration

public double GetDayOfYear()

Returns

Type	Description
Double	The day of the year in floating point double format.

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GetHashCode()

Returns the hash code for this XDate structure. In this case, the hash code is simply the equivalent hash code for the floating point double date value.

Declaration

public override int GetHashCode()

Returns

Type	Description
Int32	An integer representing the hash code for this XDate value

Overrides

ValueType.GetHashCode()

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JulianDayToCalendarDate(Double, out Int32, out Int32, out Int32, out Int32, out Int32, out Double)

Calculate a Calendar date (year, month, day, hour, minute, second) corresponding to the Astronomical Julian Day number

Declaration

public static void JulianDayToCalendarDate(double jDay, out int year, out int month, out int day, out int hour, out int minute, out double second)

Parameters

Type	Name	Description
Double	jDay	The Astronomical Julian Day number to be converted
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Double	second	The double second value (e.g., 42.3 for 42.3 seconds past the minute).

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JulianDayToCalendarDate(Double, out Int32, out Int32, out Int32, out Int32, out Int32, out Int32)

Calculate a Calendar date (year, month, day, hour, minute, second) corresponding to the Astronomical Julian Day number

Declaration

public static void JulianDayToCalendarDate(double jDay, out int year, out int month, out int day, out int hour, out int minute, out int second)

Parameters

Type	Name	Description
Double	jDay	The Astronomical Julian Day number to be converted
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Int32	second	The integer second value (e.g., 42 for 42 seconds past the minute).

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JulianDayToCalendarDate(Double, out Int32, out Int32, out Int32, out Int32, out Int32, out Int32, out Double)

Calculate a Calendar date (year, month, day, hour, minute, second) corresponding to the Astronomical Julian Day number

Declaration

public static void JulianDayToCalendarDate(double jDay, out int year, out int month, out int day, out int hour, out int minute, out int second, out double millisecond)

Parameters

Type	Name	Description
Double	jDay	The Astronomical Julian Day number to be converted
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Int32	second	The integer second value (e.g., 42 for 42 seconds past the minute).
Double	millisecond	The Double millisecond value (e.g., 342.5 for 342.5 milliseconds past the second).

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JulianDayToXLDate(Double)

Calculate an XL Date corresponding to the specified Astronomical Julian Day number

Declaration

public static double JulianDayToXLDate(double jDay)

Parameters

Type	Name	Description
Double	jDay	The Astronomical Julian Day number in floating point double format.

Returns

Type	Description
Double	The corresponding XL Date, expressed in double floating point format

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MakeValidDate(Double)

Take the specified date, and bound it to the valid date range for the XDate struct.

Declaration

public static double MakeValidDate(double xlDate)

Parameters

Type	Name	Description
Double	xlDate	The date to be bounded

Returns

Type	Description
Double	An XLDate value that lies between the minimum and maximum valid date ranges (see XLDayMin and XLDayMax)

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SetDate(Int32, Int32, Int32)

Set the calendar date (year, month, day) of this instance.

Declaration

public void SetDate(int year, int month, int day)

Parameters

Type	Name	Description
Int32	year	An integer value for the year, e.g., 1995.
Int32	month	An integer value for the month of the year, e.g., 8 for August.
Int32	day	An integer value for the day of the month, e.g., 23.

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SetDate(Int32, Int32, Int32, Int32, Int32, Int32)

Set the calendar date (year, month, day, hour, minute, second) of this instance.

Declaration

public void SetDate(int year, int month, int day, int hour, int minute, int second)

Parameters

Type	Name	Description
Int32	year	An integer value for the year, e.g., 1995.
Int32	month	An integer value for the month of the year, e.g., 8 for August.
Int32	day	An integer value for the day of the month, e.g., 23.
Int32	hour	An integer value for the hour of the day, e.g. 15.
Int32	minute	An integer value for the minute, e.g. 45.
Int32	second	An integer value for the second, e.g. 35.

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ToString()

Format this XDate value using the default format string (see cref="DefaultFormatStr"/>).

Declaration

public override string ToString()

Returns

Type	Description
String	A string representation of the date

Overrides

ValueType.ToString()

Remarks

The formatting is done using the DateTime ToString(String) method in order to provide full localization capability. The DateTime struct is limited to dates from 1 AD onward. However, all calendar dates in XDate and DateTime are projected Gregorian calendar dates. Since the Gregorian calendar was not implemented until October 4, 1582 (or later in some countries), Gregorian dates prior to that time are really dates that would have been, had the Gregorian calendar existed. In order to avoid throwing an exception, for dates prior to 1 AD, the year will be converted to a positive year and the text "(BC)" is appended to the end of the formatted string. Under this mode, the year sequence is 2BC, 1BC, 1AD, 2AD, etc. There is no year zero.

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ToString(Double)

Format this XDate value using the default format string (DefaultFormatStr).

Declaration

public string ToString(double xlDate)

Parameters

Type	Name	Description
Double	xlDate	The XL date value to be formatted in floating point double format.

Returns

Type	Description
String	A string representation of the date

Remarks

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ToString(Double, String)

Format the specified XL Date value using the specified format string. The format string is specified according to the DateTime class.

Declaration

public static string ToString(double xlDate, string fmtStr)

Parameters

Type	Name	Description
Double	xlDate	The XL date value to be formatted in floating point double format.
String	fmtStr	The formatting string to be used for the date. See DateTimeFormatInfo for a list of the format types available.

Returns

Type	Description
String	A string representation of the date

Remarks

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ToString(String)

Format this XL Date value using the specified format string. The format string is specified according to the DateTime class.

Declaration

public string ToString(string fmtStr)

Parameters

Type	Name	Description
String	fmtStr	The formatting string to be used for the date. See DateTimeFormatInfo class for a list of the format types available.

Returns

Type	Description
String	A string representation of the date

Remarks

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XLDateToCalendarDate(Double, out Int32, out Int32, out Int32, out Int32, out Int32, out Double)

Calculate a Calendar date (year, month, day, hour, minute, second) corresponding to the specified XL date

Declaration

public static void XLDateToCalendarDate(double xlDate, out int year, out int month, out int day, out int hour, out int minute, out double second)

Parameters

Type	Name	Description
Double	xlDate	The XL date value in floating point double format.
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Double	second	The double second value (e.g., 42.3 for 42.3 seconds past the minute).

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XLDateToCalendarDate(Double, out Int32, out Int32, out Int32, out Int32, out Int32, out Int32)

Calculate a Calendar date (year, month, day, hour, minute, second) corresponding to the specified XL date

Declaration

public static void XLDateToCalendarDate(double xlDate, out int year, out int month, out int day, out int hour, out int minute, out int second)

Parameters

Type	Name	Description
Double	xlDate	The XL date value in floating point double format.
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Int32	second	The integer second value (e.g., 42 for 42 seconds past the minute).

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XLDateToCalendarDate(Double, out Int32, out Int32, out Int32, out Int32, out Int32, out Int32, out Int32)

Calculate a Calendar date (year, month, day, hour, minute, second) corresponding to the specified XL date

Declaration

public static void XLDateToCalendarDate(double xlDate, out int year, out int month, out int day, out int hour, out int minute, out int second, out int millisecond)

Parameters

Type	Name	Description
Double	xlDate	The XL date value in floating point double format.
Int32	year	The integer year value (e.g., 1994).
Int32	month	The integer month value (e.g., 7 for July).
Int32	day	The integer day value (e.g., 19 for the 19th day of the month).
Int32	hour	The integer hour value (e.g., 14 for 2:00 pm).
Int32	minute	The integer minute value (e.g., 35 for 35 minutes past the hour).
Int32	second	The integer second value (e.g., 42 for 42 seconds past the minute).
Int32	millisecond	The integer millisecond value (e.g., 325 for 325 milliseconds past the second).

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XLDateToDateTime(Double)

Convert an XL date format to a .Net DateTime struct

Declaration

public static DateTime XLDateToDateTime(double xlDate)

Parameters

Type	Name	Description
Double	xlDate	The XL date value in floating point double format.

Returns

Type	Description
DateTime	The corresponding XL Date, expressed in double floating point format

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XLDateToDayOfWeek(Double)

Calculate a day-of-week value (e.g., Sun=0, Mon=1, Tue=2, etc.) corresponding to the specified XL date

Declaration

public static int XLDateToDayOfWeek(double xlDate)

Parameters

Type	Name	Description
Double	xlDate	The XL date value in floating point double format.

Returns

Type	Description
Int32	The corresponding day-of-week (DoW) value, expressed in integer format

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XLDateToDayOfYear(Double)

Calculate a day-of-year value (e.g., 241.543 corresponds to the 241st day of the year) corresponding to the specified XL date

Declaration

public static double XLDateToDayOfYear(double xlDate)

Parameters

Type	Name	Description
Double	xlDate	The XL date value in floating point double format.

Returns

Type	Description
Double	The corresponding day-of-year (DoY) value, expressed in double floating point format

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XLDateToDecimalYear(Double)

Calculate a decimal year value (e.g., 1994.6523) corresponding to the specified XL date

Declaration

public static double XLDateToDecimalYear(double xlDate)

Parameters

Type	Name	Description
Double	xlDate	The XL date value in floating point double format.

Returns

Type	Description
Double	The corresponding decimal year value, expressed in double floating point format

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XLDateToJulianDay(Double)

Calculate an Astronomical Julian Day number corresponding to the specified XL date

Declaration

public static double XLDateToJulianDay(double xlDate)

Parameters

Type	Name	Description
Double	xlDate	The XL date value in floating point double format.

Returns

Type	Description
Double	The corresponding Astronomical Julian Day number, expressed in double floating point format

Operators

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Addition(XDate, Double)

'+' operator overload. When a double value is added to an XDate, the result is a new XDate with the number of days added.

Declaration

public static XDate operator +(XDate lhs, double rhs)

Parameters

Type	Name	Description
XDate	lhs	The left-hand-side of the '-' operator (an XDate class)
Double	rhs	The right-hand-side of the '+' operator (a double value)

Returns

Type	Description
XDate	An XDate with the rhs number of days added

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Decrement(XDate)

'--' operator overload. Decrement the date by one day.

Declaration

public static XDate operator --(XDate xDate)

Parameters

Type	Name	Description
XDate	xDate	The XDate struct on which to operate

Returns

Type	Description
XDate	An XDate one day prior to the specified date

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Implicit(DateTime to XDate)

Implicit conversion from DateTime to XDate.

Declaration

public static implicit operator XDate(DateTime dt)

Parameters

Type	Name	Description
DateTime	dt	The DateTime struct on which to operate

Returns

Type	Description
XDate	An XDate struct representing the specified DateTime value.

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Implicit(Double to XDate)

Implicit conversion from double (an XL Date) to XDate.

Declaration

public static implicit operator XDate(double xlDate)

Parameters

Type	Name	Description
Double	xlDate	The XDate struct on which to operate

Returns

Type	Description
XDate	An XDate struct representing the specified xlDate value.

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Implicit(XDate to DateTime)

Implicit conversion from XDate to DateTime.

Declaration

public static implicit operator DateTime(XDate xDate)

Parameters

Type	Name	Description
XDate	xDate	The XDate struct on which to operate

Returns

Type	Description
DateTime	A DateTime struct representing the specified xDate value.

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Implicit(XDate to Double)

Implicit conversion from XDate to double (an XL Date).

Declaration

public static implicit operator double (XDate xDate)

Parameters

Type	Name	Description
XDate	xDate	The XDate struct on which to operate

Returns

Type	Description
Double	A double floating point value representing the XL Date

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Implicit(XDate to Single)

Implicit conversion from XDate to float (an XL Date).

Declaration

public static implicit operator float (XDate xDate)

Parameters

Type	Name	Description
XDate	xDate	The XDate struct on which to operate

Returns

Type	Description
Single	A double floating point value representing the XL Date

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Increment(XDate)

'++' operator overload. Increment the date by one day.

Declaration

public static XDate operator ++(XDate xDate)

Parameters

Type	Name	Description
XDate	xDate	The XDate struct on which to operate

Returns

Type	Description
XDate	An XDate one day later than the specified date

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Subtraction(XDate, Double)

'-' operator overload. When a double value is subtracted from an XDate, the result is a new XDate with the number of days subtracted.

Declaration

public static XDate operator -(XDate lhs, double rhs)

Parameters

Type	Name	Description
XDate	lhs	The left-hand-side of the '-' operator (an XDate class)
Double	rhs	The right-hand-side of the '-' operator (a double value)

Returns

Type	Description
XDate	An XDate with the rhs number of days subtracted

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Subtraction(XDate, XDate)

'-' operator overload. When two XDates are subtracted, the number of days between dates is returned.

Declaration

public static double operator -(XDate lhs, XDate rhs)

Parameters

Type	Name	Description
XDate	lhs	The left-hand-side of the '-' operator (an XDate class)
XDate	rhs	The right-hand-side of the '-' operator (an XDate class)

Returns

Type	Description
Double	The days between dates, expressed as a floating point double

Implements

System.IComparable