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SimpleDateFormat Class

Definition

SimpleDateFormat is a concrete class for formatting and parsing dates in a locale-sensitive manner.

[Android.Runtime.Register("java/text/SimpleDateFormat", DoNotGenerateAcw=true)]
public class SimpleDateFormat : Java.Text.DateFormat
[<Android.Runtime.Register("java/text/SimpleDateFormat", DoNotGenerateAcw=true)>]
type SimpleDateFormat = class
    inherit DateFormat
Inheritance
SimpleDateFormat
Attributes

Remarks

SimpleDateFormat is a concrete class for formatting and parsing dates in a locale-sensitive manner. It allows for formatting (date &rarr; text), parsing (text &rarr; date), and normalization.

SimpleDateFormat allows you to start by choosing any user-defined patterns for date-time formatting. However, you are encouraged to create a date-time formatter with either getTimeInstance, getDateInstance, or getDateTimeInstance in DateFormat. Each of these class methods can return a date/time formatter initialized with a default format pattern. You may modify the format pattern using the applyPattern methods as desired. For more information on using these methods, see DateFormat.

<h2>Date and Time Patterns</h2>

Date and time formats are specified by <em>date and time pattern</em> strings. Within date and time pattern strings, unquoted letters from 'A' to 'Z' and from 'a' to 'z' are interpreted as pattern letters representing the components of a date or time string. Text can be quoted using single quotes (') to avoid interpretation. "''" represents a single quote. All other characters are not interpreted; they're simply copied into the output string during formatting or matched against the input string during parsing.

The following pattern letters are defined (all other characters from 'A' to 'Z' and from 'a' to 'z' are reserved): <blockquote> <table class="striped"> <caption style="display:none">Chart shows pattern letters, date/time component, presentation, and examples.</caption> <thead> <tr> <th scope="col" style="text-align:left">Letter <th scope="col" style="text-align:left">Date or Time Component <th scope="col" style="text-align:left">Presentation <th scope="col" style="text-align:left">Examples <th scope="col" style="text-align:left">Supported (API Levels) </thead> <tbody> <tr> <th scope="row">G<td>Era designator <td>Text<td>AD<td>1+</td> <tr> <th scope="row">y<td>Year <td>Year<td>1996; 96<td>1+</td> <tr> <th scope="row">Y<td>Week year <td>Year<td>2009; 09<td>24+</td> <tr> <th scope="row">M<td>Month in year (context sensitive) <td>Month<td>July; Jul; 07<td>1+</td> <tr> <th scope="row">L<td>Month in year (standalone form) <td>Month<td>July; Jul; 07<td>TBD</td> <tr> <th scope="row">w<td>Week in year <td>Number<td>27<td>1+</td> <tr> <th scope="row">W<td>Week in month <td>Number<td>2<td>1+</td> <tr> <th scope="row">D<td>Day in year <td>Number<td>189<td>1+</td> <tr> <th scope="row">d<td>Day in month <td>Number<td>10<td>1+</td> <tr> <th scope="row">F<td>Day of week in month <td>Number<td>2<td>1+</td> <tr> <th scope="row">E<td>Day name in week <td>Text<td>Tuesday; Tue<td>1+</td> <tr> <th scope="row">u<td>Day number of week (1 = Monday, ..., 7 = Sunday) <td>Number<td>1<td>24+</td> <tr> <th scope="row">a<td>Am/pm marker <td>Text<td>PM<td>1+</td> <tr> <th scope="row">H<td>Hour in day (0-23) <td>Number<td>0<td>1+</td> <tr> <th scope="row">k<td>Hour in day (1-24) <td>Number<td>24<td>1+</td> <tr> <th scope="row">K<td>Hour in am/pm (0-11) <td>Number<td>0<td>1+</td> <tr> <th scope="row">h<td>Hour in am/pm (1-12) <td>Number<td>12<td>1+</td> <tr> <th scope="row">m<td>Minute in hour <td>Number<td>30<td>1+</td> <tr> <th scope="row">s<td>Second in minute <td>Number<td>55<td>1+</td> <tr> <th scope="row">S<td>Millisecond <td>Number<td>978<td>1+</td> <tr> <th scope="row">z<td>Time zone <td>General time zone<td>Pacific Standard Time; PST; GMT-08:00<td>1+</td> <tr> <th scope="row">Z<td>Time zone <td>RFC 822 time zone<td>-0800<td>1+</td> <tr> <th scope="row">X<td>Time zone <td>ISO 8601 time zone<td>-08; -0800; -08:00<td>24+</td> </tbody> </table> </blockquote> Pattern letters are usually repeated, as their number determines the exact presentation: <ul> <li><strong>"text">Text:</strong> For formatting, if the number of pattern letters is 4 or more, the full form is used; otherwise a short or abbreviated form is used if available. For parsing, both forms are accepted, independent of the number of pattern letters.</li> <li><strong>"number">Number:</strong> For formatting, the number of pattern letters is the minimum number of digits, and shorter numbers are zero-padded to this amount. For parsing, the number of pattern letters is ignored unless it's needed to separate two adjacent fields.</li> <li><strong>"year">Year:</strong> If the formatter's #getCalendar() Calendar is the Gregorian calendar, the following rules are applied. <ul> <li>For formatting, if the number of pattern letters is 2, the year is truncated to 2 digits; otherwise it is interpreted as a number. <li>For parsing, if the number of pattern letters is more than 2, the year is interpreted literally, regardless of the number of digits. So using the pattern "MM/dd/yyyy", "01/11/12" parses to Jan 11, 12 A.D. <li>For parsing with the abbreviated year pattern ("y" or "yy"), SimpleDateFormat must interpret the abbreviated year relative to some century. It does this by adjusting dates to be within 80 years before and 20 years after the time the SimpleDateFormat instance is created. For example, using a pattern of "MM/dd/yy" and a SimpleDateFormat instance created on Jan 1, 1997, the string "01/11/12" would be interpreted as Jan 11, 2012 while the string "05/04/64" would be interpreted as May 4, 1964. During parsing, only strings consisting of exactly two digits, as defined by Character#isDigit(char), will be parsed into the default century. Any other numeric string, such as a one digit string, a three or more digit string, or a two digit string that isn't all digits (for example, "-1"), is interpreted literally. So "01/02/3" or "01/02/003" are parsed, using the same pattern, as Jan 2, 3 AD. Likewise, "01/02/-3" is parsed as Jan 2, 4 BC. </ul> Otherwise, calendar system specific forms are applied. For both formatting and parsing, if the number of pattern letters is 4 or more, a calendar specific Calendar#LONG long form is used. Otherwise, a calendar specific Calendar#SHORT short or abbreviated form is used. <br> If week year 'Y' is specified and the #getCalendar() calendar doesn't support any week years, the calendar year ('y') is used instead. The support of week years can be tested with a call to DateFormat#getCalendar() getCalendar().java.util.Calendar#isWeekDateSupported() isWeekDateSupported().</li> <li><strong>"month">Month:</strong> If the number of pattern letters is 3 or more, the month is interpreted as text; otherwise, it is interpreted as a number. <ul> <li>Letter <em>M</em> produces context-sensitive month names, such as the embedded form of names. Letter <em>M</em> is context-sensitive in the sense that when it is used in the standalone pattern, for example, "MMMM", it gives the standalone form of a month name and when it is used in the pattern containing other field(s), for example, "d MMMM", it gives the format form of a month name. For example, January in the Catalan language is "de gener" in the format form while it is "gener" in the standalone form. In this case, "MMMM" will produce "gener" and the month part of the "d MMMM" will produce "de gener". If a DateFormatSymbols has been set explicitly with constructor #SimpleDateFormat(String,DateFormatSymbols) or method #setDateFormatSymbols(DateFormatSymbols), the month names given by the DateFormatSymbols are used.</li> <li>Letter <em>L</em> produces the standalone form of month names.</li> </ul> <br></li> <li><strong>"timezone">General time zone:</strong> Time zones are interpreted as text if they have names. For time zones representing a GMT offset value, the following syntax is used:

<a id="GMTOffsetTimeZone"><i>GMTOffsetTimeZone:</i></a>
                        {@code GMT} <i>Sign</i> <i>Hours</i> {@code :} <i>Minutes</i>
<i>Sign:</i> one of
                        {@code + -}
<i>Hours:</i>
<i>Digit</i>
<i>Digit</i> <i>Digit</i>
<i>Minutes:</i>
<i>Digit</i> <i>Digit</i>
<i>Digit:</i> one of
                        {@code 0 1 2 3 4 5 6 7 8 9}

Hours must be between 0 and 23, and Minutes must be between 00 and 59. The format is locale independent and digits must be taken from the Basic Latin block of the Unicode standard.

For parsing, RFC 822 time zones are also accepted.</li> <li><strong>"rfc822timezone">RFC 822 time zone:</strong> For formatting, the RFC 822 4-digit time zone format is used:

<i>RFC822TimeZone:</i>
<i>Sign</i> <i>TwoDigitHours</i> <i>Minutes</i>
<i>TwoDigitHours:</i>
<i>Digit Digit</i>

TwoDigitHours must be between 00 and 23. Other definitions are as for general time zones.

For parsing, general time zones are also accepted. <li><strong>"iso8601timezone">ISO 8601 Time zone:</strong> The number of pattern letters designates the format for both formatting and parsing as follows:

<i>ISO8601TimeZone:</i>
<i>OneLetterISO8601TimeZone</i>
<i>TwoLetterISO8601TimeZone</i>
<i>ThreeLetterISO8601TimeZone</i>
<i>OneLetterISO8601TimeZone:</i>
<i>Sign</i> <i>TwoDigitHours</i>
                        {@code Z}
<i>TwoLetterISO8601TimeZone:</i>
<i>Sign</i> <i>TwoDigitHours</i> <i>Minutes</i>
                        {@code Z}
<i>ThreeLetterISO8601TimeZone:</i>
<i>Sign</i> <i>TwoDigitHours</i> {@code :} <i>Minutes</i>
                        {@code Z}

Other definitions are as for general time zones or RFC 822 time zones.

For formatting, if the offset value from GMT is 0, "Z" is produced. If the number of pattern letters is 1, any fraction of an hour is ignored. For example, if the pattern is "X" and the time zone is "GMT+05:30", "+05" is produced.

For parsing, the letter "Z" is parsed as the UTC time zone designator (therefore "09:30Z" is parsed as "09:30 UTC". General time zones are <em>not</em> accepted.

If the number of "X" pattern letters is 4 or more (e.g. XXXX), IllegalArgumentException is thrown when constructing a SimpleDateFormat or #applyPattern(String) applying a pattern. </ul> SimpleDateFormat also supports <em>localized date and time pattern</em> strings. In these strings, the pattern letters described above may be replaced with other, locale dependent, pattern letters. SimpleDateFormat does not deal with the localization of text other than the pattern letters; that's up to the client of the class.

<h3>Examples</h3>

The following examples show how date and time patterns are interpreted in the U.S. locale. The given date and time are 2001-07-04 12:08:56 local time in the U.S. Pacific Time time zone. <blockquote> <table class="striped"> <caption style="display:none">Examples of date and time patterns interpreted in the U.S. locale</caption> <thead> <tr> <th scope="col" style="text-align:left">Date and Time Pattern <th scope="col" style="text-align:left">Result </thead> <tbody> <tr> <th scope="row">"yyyy.MM.dd G 'at' HH:mm:ss z"<td>2001.07.04 AD at 12:08:56 PDT<tr> <th scope="row">"EEE, MMM d, ''yy"<td>Wed, Jul 4, '01<tr> <th scope="row">"h:mm a"<td>12:08 PM<tr> <th scope="row">"hh 'o''clock' a, zzzz"<td>12 o'clock PM, Pacific Daylight Time<tr> <th scope="row">"K:mm a, z"<td>0:08 PM, PDT<tr> <th scope="row">"yyyyy.MMMMM.dd GGG hh:mm aaa"<td>02001.July.04 AD 12:08 PM<tr> <th scope="row">"EEE, d MMM yyyy HH:mm:ss Z"<td>Wed, 4 Jul 2001 12:08:56 -0700<tr> <th scope="row">"yyMMddHHmmssZ"<td>010704120856-0700<tr> <th scope="row">"yyyy-MM-dd'T'HH:mm:ss.SSSZ"<td>2001-07-04T12:08:56.235-0700<tr> <th scope="row">"yyyy-MM-dd'T'HH:mm:ss.SSSXXX"<td>2001-07-04T12:08:56.235-07:00<tr> <th scope="row">"YYYY-'W'ww-u"<td>2001-W27-3</tbody> </table> </blockquote>

<h3>"synchronization">Synchronization</h3>

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.SimpleDateFormat.

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

SimpleDateFormat()

Constructs a SimpleDateFormat using the default pattern and date format symbols for the default java.util.Locale.Category#FORMAT FORMAT locale.

SimpleDateFormat(IntPtr, JniHandleOwnership)

A constructor used when creating managed representations of JNI objects; called by the runtime.

SimpleDateFormat(String, DateFormatSymbols)

Constructs a SimpleDateFormat using the given pattern and date format symbols.

SimpleDateFormat(String, Locale)

Constructs a SimpleDateFormat using the given pattern and the default date format symbols for the given locale.

SimpleDateFormat(String)

Constructs a SimpleDateFormat using the given pattern and the default date format symbols for the default java.util.Locale.Category#FORMAT FORMAT locale.

Fields

AmPmField

Useful constant for AM_PM field alignment.

(Inherited from DateFormat)
DateField

Useful constant for DATE field alignment.

(Inherited from DateFormat)
DayOfWeekField

Useful constant for DAY_OF_WEEK field alignment.

(Inherited from DateFormat)
DayOfWeekInMonthField

Useful constant for DAY_OF_WEEK_IN_MONTH field alignment.

(Inherited from DateFormat)
DayOfYearField

Useful constant for DAY_OF_YEAR field alignment.

(Inherited from DateFormat)
Default

Constant for default style pattern.

(Inherited from DateFormat)
EraField

Useful constant for ERA field alignment.

(Inherited from DateFormat)
Full

Constant for full style pattern.

(Inherited from DateFormat)
Hour0Field

Useful constant for zero-based HOUR field alignment.

(Inherited from DateFormat)
Hour1Field

Useful constant for one-based HOUR field alignment.

(Inherited from DateFormat)
HourOfDay0Field

Useful constant for zero-based HOUR_OF_DAY field alignment.

(Inherited from DateFormat)
HourOfDay1Field

Useful constant for one-based HOUR_OF_DAY field alignment.

(Inherited from DateFormat)
Long

Constant for long style pattern.

(Inherited from DateFormat)
Medium

Constant for medium style pattern.

(Inherited from DateFormat)
MillisecondField

Useful constant for MILLISECOND field alignment.

(Inherited from DateFormat)
MinuteField

Useful constant for MINUTE field alignment.

(Inherited from DateFormat)
MonthField

Useful constant for MONTH field alignment.

(Inherited from DateFormat)
SecondField

Useful constant for SECOND field alignment.

(Inherited from DateFormat)
Short

Constant for short style pattern.

(Inherited from DateFormat)
TimezoneField

Useful constant for TIMEZONE field alignment.

(Inherited from DateFormat)
WeekOfMonthField

Useful constant for WEEK_OF_MONTH field alignment.

(Inherited from DateFormat)
WeekOfYearField

Useful constant for WEEK_OF_YEAR field alignment.

(Inherited from DateFormat)
YearField

Useful constant for YEAR field alignment.

(Inherited from DateFormat)

Properties

Calendar

Gets the calendar associated with this date/time formatter. -or- Set the calendar to be used by this date format.

(Inherited from DateFormat)
Class

Returns the runtime class of this Object.

(Inherited from Object)
DateFormatSymbols

Gets a copy of the date and time format symbols of this date format. -or- Sets the date and time format symbols of this date format.

Handle

The handle to the underlying Android instance.

(Inherited from Object)
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.

(Inherited from DateFormat)
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.

(Inherited from DateFormat)
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.

TimeZone

Gets the time zone. -or- Sets the time zone for the calendar of this DateFormat object.

(Inherited from DateFormat)

Methods

ApplyLocalizedPattern(String)

Applies the given localized pattern string to this date format.

ApplyPattern(String)

Applies the given pattern string to this date format.

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, StringBuffer, FieldPosition)

Formats the given Date into a date/time string and appends the result to the given StringBuffer.

Format(Date)

Formats a Date into a date-time string.

(Inherited from DateFormat)
Format(Object, StringBuffer, FieldPosition)

Formats the given Object into a date-time string.

(Inherited from DateFormat)
Format(Object)

Formats an object to produce a string.

(Inherited from _Format)
FormatToCharacterIterator(Object)

Formats an Object producing an AttributedCharacterIterator.

(Inherited from _Format)
Get2DigitYearStart()

Returns the beginning date of the 100-year period 2-digit years are interpreted as being within.

GetHashCode()

Returns a hash code value for the object.

(Inherited from Object)
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, ParsePosition)

Parses text from a string to produce a Date.

Parse(String)

Parses text from the beginning of the given string to produce a date.

(Inherited from DateFormat)
ParseObject(String, ParsePosition)

Parses text from a string to produce a Date.

(Inherited from DateFormat)
ParseObject(String)

Parses text from the beginning of the given string to produce an object.

(Inherited from _Format)
Set2DigitYearStart(Date)

Sets the 100-year period 2-digit years will be interpreted as being in to begin on the date the user specifies.

SetHandle(IntPtr, JniHandleOwnership)

Sets the Handle property.

(Inherited from Object)
ToArray<T>() (Inherited from Object)
ToLocalizedPattern()

Returns a localized pattern string describing this date format.

ToPattern()

Returns a pattern string describing this date format.

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, 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)
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)

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