Struct YearMonth

A year and month in a particular calendar. This is effectively LocalDate without the day-of-month component.

Since 3.0.x

Availability net6.0, netstandard2.0

Implements

IEquatable<YearMonth>

IComparable<YearMonth>

IComparable

IFormattable

IXmlSerializable

Inherited Members

object.Equals(object, object)

object.GetType()

object.ReferenceEquals(object, object)

Namespace: NodaTime

Assembly: NodaTime.dll

Syntax

[TypeConverter(typeof(YearMonthTypeConverter))]
public struct YearMonth : IEquatable<YearMonth>, IComparable<YearMonth>, IComparable, IFormattable, IXmlSerializable

Remarks

Values can freely be compared for equality: a value in a different calendar system is not equal to a value in a different calendar system. However, ordering comparisons fail with ArgumentException; attempting to compare values in different calendars almost always indicates a bug in the calling code.

Constructors

YearMonth(Era, int, int, CalendarSystem)

Constructs an instance for the given era, year of era and month in the specified calendar.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public YearMonth(Era era, int yearOfEra, int month, CalendarSystem calendar)

Parameters

Type	Name	Description
Era	era	The era within which to create a year/month. Must be a valid era within the specified calendar.
int	yearOfEra	The year of era.
int	month	The month of year.
CalendarSystem	calendar	Calendar system in which to create the year/month.

Remarks

Sample snippet

using NodaTime;
using NodaTime.Calendars;
using System;

YearMonth yearMonth = new YearMonth(Era.Common, 2019, 5, CalendarSystem.Gregorian);
Console.WriteLine(yearMonth.Year);
Console.WriteLine(yearMonth.Month);
Console.WriteLine(yearMonth.Calendar);
Console.WriteLine(yearMonth.Era);

Output:

2019
5
Gregorian
CE

Exceptions

Type	Condition
ArgumentOutOfRangeException	The parameters do not form a valid year/month.

YearMonth(Era, int, int)

Constructs an instance for the given era, year of era and month in the ISO calendar.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public YearMonth(Era era, int yearOfEra, int month)

Parameters

Type	Name	Description
Era	era	The era within which to create a year/month. Must be a valid era within the ISO calendar.
int	yearOfEra	The year of era.
int	month	The month of year.

Remarks

Sample snippet

using NodaTime;
using NodaTime.Calendars;
using System;

YearMonth yearMonth = new YearMonth(Era.Common, 1994, 5);
Console.WriteLine(yearMonth.Year);
Console.WriteLine(yearMonth.Month);
Console.WriteLine(yearMonth.Calendar);
Console.WriteLine(yearMonth.Era);

Output:

1994
5
ISO
CE

Exceptions

Type	Condition
ArgumentOutOfRangeException	The parameters do not form a valid year/month.

YearMonth(int, int, CalendarSystem)

Constructs an instance for the given year and month in the specified calendar.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public YearMonth(int year, int month, CalendarSystem calendar)

Parameters

Type	Name	Description
int	year	The year. This is the "absolute year", so, for the ISO calendar, a value of 0 means 1 BC, for example.
int	month	The month of year.
CalendarSystem	calendar	Calendar system in which to create the year/month.

Remarks

Sample snippet

using NodaTime;
using System;

YearMonth yearMonth = new YearMonth(2014, 3, CalendarSystem.Julian);
Console.WriteLine(yearMonth.Year);
Console.WriteLine(yearMonth.Month);
Console.WriteLine(yearMonth.Calendar);

Output:

2014
3
Julian

Exceptions

Type	Condition
ArgumentOutOfRangeException	The parameters do not form a valid year/month.

YearMonth(int, int)

Constructs an instance for the given year and month in the ISO calendar.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public YearMonth(int year, int month)

Parameters

Type	Name	Description
int	year	The year. This is the "absolute year", so a value of 0 means 1 BC, for example.
int	month	The month of year.

Remarks

Sample snippet

using NodaTime;
using System;

YearMonth yearMonth = new YearMonth(2019, 5);
Console.WriteLine(yearMonth.Year);
Console.WriteLine(yearMonth.Month);
Console.WriteLine(yearMonth.Calendar);

Output:

2019
5
ISO

Exceptions

Type	Condition
ArgumentOutOfRangeException	The parameters do not form a valid year/month.

Properties

Calendar

Gets the calendar system associated with this year/month.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public CalendarSystem Calendar { get; }

Property Value

Type	Description
CalendarSystem	The calendar system associated with this year/month.

Remarks

Era

Gets the era of this year/month.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public Era Era { get; }

Property Value

Type	Description
Era	The era of this year/month.

Remarks

Month

Gets the month of this year/month within the year.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public int Month { get; }

Property Value

Type	Description
int	The month of this year/month within the year.

Remarks

Year

Gets the year of this year/month.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public int Year { get; }

Property Value

Type	Description
int	The year of this year/month.

Remarks

This returns the "absolute year", so, for the ISO calendar, a value of 0 means 1 BC, for example.

YearOfEra

Gets the year of this value within the era.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public int YearOfEra { get; }

Property Value

Type	Description
int	The year of this value within the era.

Remarks

Methods

AddSchema(XmlSchemaSet)

Adds the XML schema type describing the structure of the YearMonth XML serialization to the given xmlSchemaSet.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public static XmlQualifiedName AddSchema(XmlSchemaSet xmlSchemaSet)

Parameters

Type	Name	Description
XmlSchemaSet	xmlSchemaSet	The XML schema set provided by XmlSchemaExporter.

Returns

Type	Description
XmlQualifiedName	The qualified name of the schema type that was added to the `xmlSchemaSet`.

Remarks

CompareTo(YearMonth)

Indicates whether this year/month is earlier, later or the same as another one. See the type documentation for a description of ordering semantics.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public int CompareTo(YearMonth other)

Parameters

Type	Name	Description
YearMonth	other	The other year/month to compare this one with

Returns

Type	Description
int	A value less than zero if this year/month is earlier than `other`; zero if this year/month is the same as `other`; a value greater than zero if this date is later than `other`.

Remarks

Exceptions

Type	Condition
ArgumentException	The calendar system of `other` is not the same as the calendar system of this value.

Equals(YearMonth)

Compares two YearMonth values for equality. See the type documentation for a description of ordering semantics.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public bool Equals(YearMonth other)

Parameters

Type	Name	Description
YearMonth	other	The value to compare this year/month with.

Returns

Type	Description
bool	True if the given value is another year/month equal to this one; false otherwise.

Remarks

Equals(object?)

Compares two YearMonth values for equality. See the type documentation for a description of equality semantics.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public override bool Equals(object? obj)

Parameters

Type	Name	Description
object	obj	The object to compare this year/month with.

Returns

Type	Description
bool	True if the given value is another year/month equal to this one; false otherwise.

Overrides

ValueType.Equals(Object)

Remarks

GetHashCode()

Returns a hash code for this year/month. See the type documentation for a description of equality semantics.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public override int GetHashCode()

Returns

Type	Description
int	A hash code for this value.

Overrides

ValueType.GetHashCode()

Remarks

OnDayOfMonth(int)

Returns a LocalDate with the year/month of this value, and the given day of month.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public LocalDate OnDayOfMonth(int day)

Parameters

Type	Name	Description
int	day	The day within the month.

Returns

Type	Description
LocalDate	The result of combining this year and month with `day`.

Remarks

Exceptions

Type	Condition
ArgumentOutOfRangeException	`day` does not fall within the month represented by this value.

PlusMonths(int)

Returns a YearMonth object which is the result of adding the specified number of months to this object.

Since 3.1.x

Availability net6.0, netstandard2.0

Declaration

public YearMonth PlusMonths(int months)

Parameters

Type	Name	Description
int	months	The number of months to add to this object.

Returns

Type	Description
YearMonth	The resulting YearMonth after adding the specified number of months.

Remarks

ToDateInterval()

Returns a DateInterval covering the month represented by this value.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public DateInterval ToDateInterval()

Returns

Type	Description
DateInterval	A DateInterval covering the month represented by this value.

Remarks

Sample snippet

using NodaTime;
using System;

YearMonth yearMonth = new YearMonth(2019, 5);
DateInterval interval = yearMonth.ToDateInterval();
Console.WriteLine(interval.Start);
Console.WriteLine(interval.End);

Output:

Wednesday, 01 May 2019
Friday, 31 May 2019

ToString()

Returns a String that represents this instance.

Since 3.1.x

Availability net6.0, netstandard2.0

Declaration

public override string ToString()

Returns

Type	Description
string	The value of the current instance in the culture-specific default format pattern ("G"), using the current thread's culture to obtain a format provider.

Overrides

ValueType.ToString()

Remarks

ToString(string?, IFormatProvider?)

Formats the value of the current instance using the specified pattern.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public string ToString(string? patternText, IFormatProvider? formatProvider)

Parameters

Type	Name	Description
string	patternText	The String specifying the pattern to use, or null to use the ISO format pattern ("g").
IFormatProvider	formatProvider	The IFormatProvider to use when formatting the value, or null to use the current thread's culture to obtain a format provider.

Returns

Type	Description
string	A String containing the value of the current instance in the specified format.

Remarks

Unlike most IFormattable implementations, a patternText of null with the current thread's culture does not yield the same result as the parameterless ToString() overload, for backward-compatibility reasons. (It uses the ISO format, which is culture-insensitive.)

Operators

operator ==(YearMonth, YearMonth)

Compares two YearMonth values for equality. See the type documentation for a description of equality semantics.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public static bool operator ==(YearMonth lhs, YearMonth rhs)

Parameters

Type	Name	Description
YearMonth	lhs	The first value to compare
YearMonth	rhs	The second value to compare

Returns

Type	Description
bool	True if the two year/month values are the same and in the same calendar; false otherwise

Remarks

operator >(YearMonth, YearMonth)

Compares two YearMonth values to see if the left one is strictly later than the right one. See the type documentation for a description of ordering semantics.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public static bool operator >(YearMonth lhs, YearMonth rhs)

Parameters

Type	Name	Description
YearMonth	lhs	First operand of the comparison
YearMonth	rhs	Second operand of the comparison

Returns

Type	Description
bool	true if the `lhs` is strictly later than `rhs`, false otherwise.

Remarks

Exceptions

Type	Condition
ArgumentException	The calendar system of `rhs` is not the same as the calendar of `lhs`.

operator >=(YearMonth, YearMonth)

Compares two YearMonth values to see if the left one is later than or equal to the right one. See the type documentation for a description of ordering semantics.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public static bool operator >=(YearMonth lhs, YearMonth rhs)

Parameters

Type	Name	Description
YearMonth	lhs	First operand of the comparison
YearMonth	rhs	Second operand of the comparison

Returns

Type	Description
bool	true if the `lhs` is later than or equal to `rhs`, false otherwise.

Remarks

Exceptions

Type	Condition
ArgumentException	The calendar system of `rhs` is not the same as the calendar of `lhs`.

operator !=(YearMonth, YearMonth)

Compares two YearMonth values for inequality. See the type documentation for a description of equality semantics.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public static bool operator !=(YearMonth lhs, YearMonth rhs)

Parameters

Type	Name	Description
YearMonth	lhs	The first value to compare
YearMonth	rhs	The second value to compare

Returns

Type	Description
bool	False if the two year/month values are the same and in the same calendar; true otherwise

Remarks

operator <(YearMonth, YearMonth)

Compares two YearMonth values to see if the left one is strictly earlier than the right one. See the type documentation for a description of ordering semantics.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public static bool operator <(YearMonth lhs, YearMonth rhs)

Parameters

Type	Name	Description
YearMonth	lhs	First operand of the comparison
YearMonth	rhs	Second operand of the comparison

Returns

Type	Description
bool	true if the `lhs` is strictly earlier than `rhs`, false otherwise.

Remarks

Exceptions

Type	Condition
ArgumentException	The calendar system of `rhs` is not the same as the calendar of `lhs`.

operator <=(YearMonth, YearMonth)

Compares two YearMonth values to see if the left one is earlier than or equal to the right one. See the type documentation for a description of ordering semantics.

Since 3.0.x

Availability net6.0, netstandard2.0

Declaration

public static bool operator <=(YearMonth lhs, YearMonth rhs)

Parameters

Type	Name	Description
YearMonth	lhs	First operand of the comparison
YearMonth	rhs	Second operand of the comparison

Returns

Type	Description
bool	true if the `lhs` is earlier than or equal to `rhs`, false otherwise.

Remarks

Exceptions

Type	Condition
ArgumentException	The calendar system of `rhs` is not the same as the calendar of `lhs`.

Implements

System.IEquatable<T>

System.IComparable<T>

System.IComparable

System.IFormattable

System.Xml.Serialization.IXmlSerializable