DateFormat Class

Reference

Definition

Namespace:: Java.Text

Assembly:: Mono.Android.dll

Important

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DateFormat is an abstract class for date/time formatting subclasses which formats and parses dates or time in a language-independent manner.

[Android.Runtime.Register("java/text/DateFormat", DoNotGenerateAcw=true)]
public abstract class DateFormat : Java.Text._Format

[<Android.Runtime.Register("java/text/DateFormat", DoNotGenerateAcw=true)>]
type DateFormat = class
    inherit _Format

Inheritance: Object

Object

_Format
DateFormat

Derived: Java.Text.SimpleDateFormat

Attributes: RegisterAttribute

Remarks

DateFormat is an abstract class for date/time formatting subclasses which formats and parses dates or time in a language-independent manner. The date/time formatting subclass, such as SimpleDateFormat, allows for formatting (i.e., date → text), parsing (text → date), and normalization. The date is represented as a Date object or as the milliseconds since January 1, 1970, 00:00:00 GMT.

DateFormat provides many class methods for obtaining default date/time formatters based on the default or a given locale and a number of formatting styles. The formatting styles include #FULL, #LONG, #MEDIUM, and #SHORT. More detail and examples of using these styles are provided in the method descriptions.

DateFormat helps you to format and parse dates for any locale. Your code can be completely independent of the locale conventions for months, days of the week, or even the calendar format: lunar vs. solar.

To format a date for the current Locale, use one of the static factory methods: <blockquote>

{@code
            myString = DateFormat.getDateInstance().format(myDate);
            }

</blockquote>

If you are formatting multiple dates, it is more efficient to get the format and use it multiple times so that the system doesn't have to fetch the information about the local language and country conventions multiple times. <blockquote>

{@code
            DateFormat df = DateFormat.getDateInstance();
            for (int i = 0; i < myDate.length; ++i) {
                output.println(df.format(myDate[i]) + "; ");
            }
            }

</blockquote>

To format a date for a different Locale, specify it in the call to #getDateInstance(int, Locale) getDateInstance(). <blockquote>

{@code
            DateFormat df = DateFormat.getDateInstance(DateFormat.LONG, Locale.FRANCE);
            }

</blockquote>

You can use a DateFormat to parse also. <blockquote>

{@code
            myDate = df.parse(myString);
            }

</blockquote>

Use getDateInstance to get the normal date format for that country. There are other static factory methods available. Use getTimeInstance to get the time format for that country. Use getDateTimeInstance to get a date and time format. You can pass in different options to these factory methods to control the length of the result; from #SHORT to #MEDIUM to #LONG to #FULL. The exact result depends on the locale, but generally: <ul><li>#SHORT is completely numeric, such as 12.13.52 or 3:30pm<li>#MEDIUM is longer, such as Jan 12, 1952<li>#LONG is longer, such as January 12, 1952 or 3:30:32pm<li>#FULL is pretty completely specified, such as Tuesday, April 12, 1952 AD or 3:30:42pm PST. </ul>

You can also set the time zone on the format if you wish. If you want even more control over the format or parsing, (or want to give your users more control), you can try casting the DateFormat you get from the factory methods to a SimpleDateFormat. This will work for the majority of countries; just remember to put it in a try block in case you encounter an unusual one.

You can also use forms of the parse and format methods with ParsePosition and FieldPosition to allow you to <ul><li>progressively parse through pieces of a string. <li>align any particular field, or find out where it is for selection on the screen. </ul>

<h2>"synchronization">Synchronization</h2>

Date formats are not synchronized. It is recommended to create separate format instances for each thread. If multiple threads access a format concurrently, it must be synchronized externally.

Added in 1.1.

Java documentation for java.text.DateFormat.

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Constructors

DateFormat()	Create a new date format.
DateFormat(IntPtr, JniHandleOwnership)	A constructor used when creating managed representations of JNI objects; called by the runtime.

Fields

AmPmField	Useful constant for AM_PM field alignment.
DateField	Useful constant for DATE field alignment.
DayOfWeekField	Useful constant for DAY_OF_WEEK field alignment.
DayOfWeekInMonthField	Useful constant for DAY_OF_WEEK_IN_MONTH field alignment.
DayOfYearField	Useful constant for DAY_OF_YEAR field alignment.
Default	Constant for default style pattern.
EraField	Useful constant for ERA field alignment.
Full	Constant for full style pattern.
Hour0Field	Useful constant for zero-based HOUR field alignment.
Hour1Field	Useful constant for one-based HOUR field alignment.
HourOfDay0Field	Useful constant for zero-based HOUR_OF_DAY field alignment.
HourOfDay1Field	Useful constant for one-based HOUR_OF_DAY field alignment.
Long	Constant for long style pattern.
Medium	Constant for medium style pattern.
MillisecondField	Useful constant for MILLISECOND field alignment.
MinuteField	Useful constant for MINUTE field alignment.
MonthField	Useful constant for MONTH field alignment.
SecondField	Useful constant for SECOND field alignment.
Short	Constant for short style pattern.
TimezoneField	Useful constant for TIMEZONE field alignment.
WeekOfMonthField	Useful constant for WEEK_OF_MONTH field alignment.
WeekOfYearField	Useful constant for WEEK_OF_YEAR field alignment.
YearField	Useful constant for YEAR field alignment.

Properties

Calendar	Gets the calendar associated with this date/time formatter. -or- Set the calendar to be used by this date format.
Class	Returns the runtime class of this `Object`. (Inherited from Object)
DateInstance	Gets the date formatter with the default formatting style for the default `java.util.Locale.Category#FORMAT FORMAT` locale.
DateTimeInstance	Gets the date/time formatter with the default formatting style for the default `java.util.Locale.Category#FORMAT FORMAT` locale.
Handle	The handle to the underlying Android instance. (Inherited from Object)
Instance	Get a default date/time formatter that uses the SHORT style for both the date and the time.
JniIdentityHashCode	(Inherited from Object)
JniPeerMembers
Lenient	Tell whether date/time parsing is to be lenient. -or- Specify whether or not date/time parsing is to be lenient.
NumberFormat	Gets the number formatter which this date/time formatter uses to format and parse a time. -or- Allows you to set the number formatter.
PeerReference	(Inherited from Object)
ThresholdClass	This API supports the Mono for Android infrastructure and is not intended to be used directly from your code.
ThresholdType	This API supports the Mono for Android infrastructure and is not intended to be used directly from your code.
TimeInstance	Gets the time formatter with the default formatting style for the default `java.util.Locale.Category#FORMAT FORMAT` locale.
TimeZone	Gets the time zone. -or- Sets the time zone for the calendar of this `DateFormat` object.

Methods

Clone()	Creates and returns a copy of this object. (Inherited from _Format)
Dispose()	(Inherited from Object)
Dispose(Boolean)	(Inherited from Object)
Equals(Object)	Indicates whether some other object is "equal to" this one. (Inherited from Object)
Format(Date)	Formats a `Date` into a date-time string.
Format(Date, StringBuffer, FieldPosition)	Formats a `Date` into a date-time string.
Format(Object)	Formats an object to produce a string. (Inherited from _Format)
Format(Object, StringBuffer, FieldPosition)	Formats the given `Object` into a date-time string.
FormatToCharacterIterator(Object)	Formats an Object producing an `AttributedCharacterIterator`. (Inherited from _Format)
GetAvailableLocales()	Returns an array of all locales for which the `get*Instance` methods of this class can return localized instances.
GetDateInstance(Int32)	Gets the date formatter with the given formatting style for the default `java.util.Locale.Category#FORMAT FORMAT` locale.
GetDateInstance(Int32, Locale)	Gets the date formatter with the given formatting style for the given locale.
GetDateTimeInstance(Int32, Int32)	Gets the date/time formatter with the given date and time formatting styles for the default `java.util.Locale.Category#FORMAT FORMAT` locale.
GetDateTimeInstance(Int32, Int32, Locale)	Gets the date/time formatter with the given formatting styles for the given locale.
GetHashCode()	Returns a hash code value for the object. (Inherited from Object)
GetTimeInstance(Int32)	Gets the time formatter with the given formatting style for the default `java.util.Locale.Category#FORMAT FORMAT` locale.
GetTimeInstance(Int32, Locale)	Gets the time formatter with the given formatting style for the given locale.
JavaFinalize()	Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. (Inherited from Object)
Notify()	Wakes up a single thread that is waiting on this object's monitor. (Inherited from Object)
NotifyAll()	Wakes up all threads that are waiting on this object's monitor. (Inherited from Object)
Parse(String)	Parses text from the beginning of the given string to produce a date.
Parse(String, ParsePosition)	Parse a date/time string according to the given parse position.
ParseObject(String)	Parses text from the beginning of the given string to produce an object. (Inherited from _Format)
ParseObject(String, ParsePosition)	Parses text from a string to produce a `Date`.
SetHandle(IntPtr, JniHandleOwnership)	Sets the Handle property. (Inherited from Object)
ToArray<T>()	(Inherited from Object)
ToString()	Returns a string representation of the object. (Inherited from Object)
UnregisterFromRuntime()	(Inherited from Object)
Wait()	Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>. (Inherited from Object)
Wait(Int64)	Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed. (Inherited from Object)
Wait(Int64, Int32)	Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed. (Inherited from Object)

Explicit Interface Implementations

IJavaPeerable.Disposed()	(Inherited from Object)
IJavaPeerable.DisposeUnlessReferenced()	(Inherited from Object)
IJavaPeerable.Finalized()	(Inherited from Object)
IJavaPeerable.JniManagedPeerState	(Inherited from Object)
IJavaPeerable.SetJniIdentityHashCode(Int32)	(Inherited from Object)
IJavaPeerable.SetJniManagedPeerState(JniManagedPeerStates)	(Inherited from Object)
IJavaPeerable.SetPeerReference(JniObjectReference)	(Inherited from Object)

Extension Methods

JavaCast<TResult>(IJavaObject)	Performs an Android runtime-checked type conversion.
JavaCast<TResult>(IJavaObject)
GetJniTypeName(IJavaPeerable)

Applies to

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DateFormat Class

Definition

Remarks

Constructors

Fields

Properties

Methods

Explicit Interface Implementations

Extension Methods

Applies to

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