icu::NumberFormat Class Reference

#include "unicode/numfmt.h"

Inheritance diagram for icu::NumberFormat:

Public Types
enum	ERoundingMode { kRoundCeiling, kRoundFloor, kRoundDown, kRoundUp, kRoundHalfEven, kRoundHalfDown, kRoundHalfUp, kRoundUnnecessary }
	Rounding mode. More...
enum	EAlignmentFields { kIntegerField = UNUM_INTEGER_FIELD, kFractionField = UNUM_FRACTION_FIELD, kDecimalSeparatorField = UNUM_DECIMAL_SEPARATOR_FIELD, kExponentSymbolField = UNUM_EXPONENT_SYMBOL_FIELD, kExponentSignField = UNUM_EXPONENT_SIGN_FIELD, kExponentField = UNUM_EXPONENT_FIELD, kGroupingSeparatorField = UNUM_GROUPING_SEPARATOR_FIELD, kCurrencyField = UNUM_CURRENCY_FIELD, kPercentField = UNUM_PERCENT_FIELD, kPermillField = UNUM_PERMILL_FIELD, kSignField = UNUM_SIGN_FIELD, INTEGER_FIELD = UNUM_INTEGER_FIELD, FRACTION_FIELD = UNUM_FRACTION_FIELD }
	Alignment Field constants used to construct a FieldPosition object. More...
Public Member Functions
virtual	~NumberFormat ()
	Destructor.
virtual UBool	operator== (const Format &other) const
	Return true if the given Format objects are semantically equal.
virtual UnicodeString &	format (const Formattable &obj, UnicodeString &appendTo, FieldPosition &pos, UErrorCode &status) const
	Format an object to produce a string.
virtual UnicodeString &	format (const Formattable &obj, UnicodeString &appendTo, FieldPositionIterator *posIter, UErrorCode &status) const
	Format an object to produce a string.
virtual void	parseObject (const UnicodeString &source, Formattable &result, ParsePosition &parse_pos) const
	Parse a string to produce an object.
UnicodeString &	format (double number, UnicodeString &appendTo) const
	Format a double number.
UnicodeString &	format (int32_t number, UnicodeString &appendTo) const
	Format a long number.
UnicodeString &	format (int64_t number, UnicodeString &appendTo) const
	Format an int64 number.
virtual UnicodeString &	format (double number, UnicodeString &appendTo, FieldPosition &pos) const =0
	Format a double number.
virtual UnicodeString &	format (double number, UnicodeString &appendTo, FieldPosition &pos, UErrorCode &status) const
	Format a double number.
virtual UnicodeString &	format (double number, UnicodeString &appendTo, FieldPositionIterator *posIter, UErrorCode &status) const
	Format a double number.
virtual UnicodeString &	format (int32_t number, UnicodeString &appendTo, FieldPosition &pos) const =0
	Format a long number.
virtual UnicodeString &	format (int32_t number, UnicodeString &appendTo, FieldPosition &pos, UErrorCode &status) const
	Format a long number.
virtual UnicodeString &	format (int32_t number, UnicodeString &appendTo, FieldPositionIterator *posIter, UErrorCode &status) const
	Format an int32 number.
virtual UnicodeString &	format (int64_t number, UnicodeString &appendTo, FieldPosition &pos) const
	Format an int64 number.
virtual UnicodeString &	format (int64_t number, UnicodeString &appendTo, FieldPosition &pos, UErrorCode &status) const
	Format an int64 number.
virtual UnicodeString &	format (int64_t number, UnicodeString &appendTo, FieldPositionIterator *posIter, UErrorCode &status) const
	Format an int64 number.
virtual UnicodeString &	format (StringPiece number, UnicodeString &appendTo, FieldPositionIterator *posIter, UErrorCode &status) const
	Format a decimal number.
virtual UnicodeString &	format (const number::impl::DecimalQuantity &number, UnicodeString &appendTo, FieldPositionIterator *posIter, UErrorCode &status) const
	Format a decimal number.
virtual UnicodeString &	format (const number::impl::DecimalQuantity &number, UnicodeString &appendTo, FieldPosition &pos, UErrorCode &status) const
	Format a decimal number.
virtual void	parse (const UnicodeString &text, Formattable &result, ParsePosition &parsePosition) const =0
	Return a long if possible (e.g.
virtual void	parse (const UnicodeString &text, Formattable &result, UErrorCode &status) const
	Parse a string as a numeric value, and return a Formattable numeric object.
virtual CurrencyAmount *	parseCurrency (const UnicodeString &text, ParsePosition &pos) const
	Parses text from the given string as a currency amount.
UBool	isParseIntegerOnly (void) const
	Return true if this format will parse numbers as integers only.
virtual void	setParseIntegerOnly (UBool value)
	Sets whether or not numbers should be parsed as integers only.
virtual void	setLenient (UBool enable)
	Sets whether lenient parsing should be enabled (it is off by default).
virtual UBool	isLenient (void) const
	Returns whether lenient parsing is enabled (it is off by default).
UBool	isGroupingUsed (void) const
	Returns true if grouping is used in this format.
virtual void	setGroupingUsed (UBool newValue)
	Set whether or not grouping will be used in this format.
int32_t	getMaximumIntegerDigits (void) const
	Returns the maximum number of digits allowed in the integer portion of a number.
virtual void	setMaximumIntegerDigits (int32_t newValue)
	Sets the maximum number of digits allowed in the integer portion of a number.
int32_t	getMinimumIntegerDigits (void) const
	Returns the minimum number of digits allowed in the integer portion of a number.
virtual void	setMinimumIntegerDigits (int32_t newValue)
	Sets the minimum number of digits allowed in the integer portion of a number.
int32_t	getMaximumFractionDigits (void) const
	Returns the maximum number of digits allowed in the fraction portion of a number.
virtual void	setMaximumFractionDigits (int32_t newValue)
	Sets the maximum number of digits allowed in the fraction portion of a number.
int32_t	getMinimumFractionDigits (void) const
	Returns the minimum number of digits allowed in the fraction portion of a number.
virtual void	setMinimumFractionDigits (int32_t newValue)
	Sets the minimum number of digits allowed in the fraction portion of a number.
virtual void	setCurrency (const char16_t *theCurrency, UErrorCode &ec)
	Sets the currency used to display currency amounts.
const char16_t *	getCurrency () const
	Gets the currency used to display currency amounts.
virtual void	setContext (UDisplayContext value, UErrorCode &status)
	Set a particular UDisplayContext value in the formatter, such as UDISPCTX_CAPITALIZATION_FOR_STANDALONE.
virtual UDisplayContext	getContext (UDisplayContextType type, UErrorCode &status) const
	Get the formatter's UDisplayContext value for the specified UDisplayContextType, such as UDISPCTX_TYPE_CAPITALIZATION.
virtual ERoundingMode	getRoundingMode (void) const
	Get the rounding mode.
virtual void	setRoundingMode (ERoundingMode roundingMode)
	Set the rounding mode.
virtual UClassID	getDynamicClassID (void) const =0
	Returns a unique class ID POLYMORPHICALLY.
Static Public Member Functions
static NumberFormat *	createInstance (UErrorCode &)
	Create a default style NumberFormat for the current default locale.
static NumberFormat *	createInstance (const Locale &inLocale, UErrorCode &)
	Create a default style NumberFormat for the specified locale.
static NumberFormat *	createInstance (const Locale &desiredLocale, UNumberFormatStyle style, UErrorCode &errorCode)
	Create a specific style NumberFormat for the specified locale.
static NumberFormat *	internalCreateInstance (const Locale &desiredLocale, UNumberFormatStyle style, UErrorCode &errorCode)
	ICU use only.
static const SharedNumberFormat *	createSharedInstance (const Locale &inLocale, UNumberFormatStyle style, UErrorCode &status)
	ICU use only.
static NumberFormat *	createCurrencyInstance (UErrorCode &)
	Returns a currency format for the current default locale.
static NumberFormat *	createCurrencyInstance (const Locale &inLocale, UErrorCode &)
	Returns a currency format for the specified locale.
static NumberFormat *	createPercentInstance (UErrorCode &)
	Returns a percentage format for the current default locale.
static NumberFormat *	createPercentInstance (const Locale &inLocale, UErrorCode &)
	Returns a percentage format for the specified locale.
static NumberFormat *	createScientificInstance (UErrorCode &)
	Returns a scientific format for the current default locale.
static NumberFormat *	createScientificInstance (const Locale &inLocale, UErrorCode &)
	Returns a scientific format for the specified locale.
static const Locale *	getAvailableLocales (int32_t &count)
	Get the set of Locales for which NumberFormats are installed.
static URegistryKey	registerFactory (NumberFormatFactory *toAdopt, UErrorCode &status)
	Register a new NumberFormatFactory.
static UBool	unregister (URegistryKey key, UErrorCode &status)
	Unregister a previously-registered NumberFormatFactory using the key returned from the register call.
static StringEnumeration *	getAvailableLocales (void)
	Return a StringEnumeration over the locales available at the time of the call, including registered locales.
static UClassID	getStaticClassID (void)
	Return the class ID for this class.
Protected Member Functions
	NumberFormat ()
	Default constructor for subclass use only.
	NumberFormat (const NumberFormat &)
	Copy constructor.
NumberFormat &	operator= (const NumberFormat &)
	Assignment operator.
virtual void	getEffectiveCurrency (char16_t *result, UErrorCode &ec) const
	Returns the currency in effect for this formatter.
Static Protected Member Functions
static NumberFormat *	makeInstance (const Locale &desiredLocale, UNumberFormatStyle style, UBool mustBeDecimalFormat, UErrorCode &errorCode)
	Creates the specified number format style of the desired locale.
Static Protected Attributes
static const int32_t	gDefaultMaxIntegerDigits
static const int32_t	gDefaultMinIntegerDigits
Friends
class	ICUNumberFormatFactory
class	ICUNumberFormatService
class	::NumberFormatTest

Detailed Description

IMPORTANT: New users are strongly encouraged to see if numberformatter.h fits their use case. Although not deprecated, this header is provided for backwards compatibility only.

Abstract base class for all number formats. Provides interface for formatting and parsing a number. Also provides methods for determining which locales have number formats, and what their names are.

NumberFormat helps you to format and parse numbers for any locale. Your code can be completely independent of the locale conventions for decimal points, thousands-separators, or even the particular decimal digits used, or whether the number format is even decimal.

To format a number for the current Locale, use one of the static factory methods:

    #include <iostream>
    #include "unicode/numfmt.h"
    #include "unicode/unistr.h"
    #include "unicode/ustream.h"
    using namespace std;
    
    int main() {
        double myNumber = 7.0;
        UnicodeString myString;
        UErrorCode success = U_ZERO_ERROR;
        NumberFormat* nf = NumberFormat::createInstance(success);
        nf->format(myNumber, myString);
        cout << " Example 1: " << myString << endl;
    }

Note that there are additional factory methods within subclasses of NumberFormat.

If you are formatting multiple numbers, 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.

     UnicodeString myString;
     UErrorCode success = U_ZERO_ERROR;
     NumberFormat *nf = NumberFormat::createInstance( success );
     for (int32_t number: {123, 3333, -1234567}) {
         nf->format(number, myString);
         myString += "; ";
     }
     cout << " Example 2: " << myString << endl;

To format a number for a different Locale, specify it in the call to createInstance().

     nf = NumberFormat::createInstance(Locale::getFrench(), success);

You can use a NumberFormat to parse also.

    UErrorCode success;
    Formattable result(-999);  // initialized with error code
    nf->parse(myString, result, success);

Use createInstance() to get the normal number format for a Locale. There are other static factory methods available. Use createCurrencyInstance() to get the currency number format for that country. Use createPercentInstance() to get a format for displaying percentages. With this format, a fraction from 0.53 is displayed as 53%.

The type of number formatting can be specified by passing a 'style' parameter to createInstance(). For example, use
createInstance(locale, UNUM_DECIMAL, errorCode) to get the normal number format,
createInstance(locale, UNUM_PERCENT, errorCode) to get a format for displaying percentage,
createInstance(locale, UNUM_SCIENTIFIC, errorCode) to get a format for displaying scientific number,
createInstance(locale, UNUM_CURRENCY, errorCode) to get the currency number format, in which the currency is represented by its symbol, for example, "$3.00".
createInstance(locale, UNUM_CURRENCY_ISO, errorCode) to get the currency number format, in which the currency is represented by its ISO code, for example "USD3.00".
createInstance(locale, UNUM_CURRENCY_PLURAL, errorCode) to get the currency number format, in which the currency is represented by its full name in plural format, for example, "3.00 US dollars" or "1.00 US dollar".

You can also control the display of numbers with such methods as getMinimumFractionDigits(). If you want even more control over the format or parsing, or want to give your users more control, you can try dynamic_casting the NumberFormat you get from the factory methods to a DecimalFormat. This will work for the vast majority of countries; just remember to test for NULL 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:

(a) progressively parse through pieces of a string.
(b) align the decimal point and other areas.

For example, you can align numbers in two ways.

If you are using a monospaced font with spacing for alignment, you can pass the FieldPosition in your format call, with field = UNUM_INTEGER_FIELD. On output, getEndIndex will be set to the offset between the last character of the integer and the decimal. Add (desiredSpaceCount - getEndIndex) spaces at the front of the string.

If you are using proportional fonts, instead of padding with spaces, measure the width of the string in pixels from the start to getEndIndex. Then move the pen by (desiredPixelWidth - widthToAlignmentPoint) before drawing the text. It also works where there is no decimal, but possibly additional characters at the end, e.g. with parentheses in negative numbers: "(12)" for -12.

User subclasses are not supported. While clients may write subclasses, such code will not necessarily work and will not be guaranteed to work stably from release to release.

Stable:: ICU 2.0

Definition at line 173 of file numfmt.h.

Member Enumeration Documentation

enum icu::NumberFormat::EAlignmentFields

Alignment Field constants used to construct a FieldPosition object.

Signifies that the position of the integer part or fraction part of a formatted number should be returned.

Note: as of ICU 4.4, the values in this enum have been extended to support identification of all number format fields, not just those pertaining to alignment.

These constants are provided for backwards compatibility only. Please use the C style constants defined in the header file unum.h.

See also:: FieldPosition

Stable:: ICU 2.0

Enumerator:

kIntegerField	Stable: ICU 2.0
kFractionField	Stable: ICU 2.0
kDecimalSeparatorField	Stable: ICU 2.0
kExponentSymbolField	Stable: ICU 2.0
kExponentSignField	Stable: ICU 2.0
kExponentField	Stable: ICU 2.0
kGroupingSeparatorField	Stable: ICU 2.0
kCurrencyField	Stable: ICU 2.0
kPercentField	Stable: ICU 2.0
kPermillField	Stable: ICU 2.0
kSignField	Stable: ICU 2.0
INTEGER_FIELD	These constants are provided for backwards compatibility only. Please use the constants defined in the header file unum.h. Stable: ICU 2.0
FRACTION_FIELD	Stable: ICU 2.0

Definition at line 217 of file numfmt.h.

enum icu::NumberFormat::ERoundingMode

Rounding mode.

For more detail on rounding modes, see: http://userguide.icu-project.org/formatparse/numbers/rounding-modes

Stable:: ICU 2.4

Enumerator:

kRoundCeiling	Round towards positive infinity.
kRoundFloor	Round towards negative infinity.
kRoundDown	Round towards zero.
kRoundUp	Round away from zero.
kRoundHalfEven	Round towards the nearest integer, or towards the nearest even integer if equidistant.
kRoundHalfDown	Round towards the nearest integer, or towards zero if equidistant.
kRoundHalfUp	Round towards the nearest integer, or away from zero if equidistant.
kRoundUnnecessary	Return U_FORMAT_INEXACT_ERROR if number does not format exactly. Stable: ICU 4.8

Definition at line 184 of file numfmt.h.

Constructor & Destructor Documentation

virtual icu::NumberFormat::~NumberFormat ( ) [virtual]

Destructor.

Stable:: ICU 2.0

icu::NumberFormat::NumberFormat ( ) [protected]

Default constructor for subclass use only.

Stable:: ICU 2.0

icu::NumberFormat::NumberFormat ( const NumberFormat & ) [protected]

Copy constructor.

Stable:: ICU 2.0

Member Function Documentation

static NumberFormat* icu::NumberFormat::createCurrencyInstance	(	const Locale &	inLocale,
		UErrorCode &
	)			`[static]`

Returns a currency format for the specified locale.

NOTE: New users are strongly encouraged to use icu::number::NumberFormatter instead of NumberFormat.

Parameters:

inLocale

the given locale.

Stable:: ICU 2.0

static NumberFormat* icu::NumberFormat::createCurrencyInstance ( UErrorCode & ) [static]

Returns a currency format for the current default locale.

NOTE: New users are strongly encouraged to use icu::number::NumberFormatter instead of NumberFormat.

Stable:: ICU 2.0

static NumberFormat* icu::NumberFormat::createInstance	(	const Locale &	desiredLocale,
		UNumberFormatStyle	style,
		UErrorCode &	errorCode
	)			`[static]`

Create a specific style NumberFormat for the specified locale.

NOTE: New users are strongly encouraged to use icu::number::NumberFormatter instead of NumberFormat.

Parameters:

	desiredLocale	the given locale.
	style	the given style.
	errorCode	Output param filled with success/failure status.

Returns:: A new NumberFormat instance.

Stable:: ICU 4.8

static NumberFormat* icu::NumberFormat::createInstance	(	const Locale &	inLocale,
		UErrorCode &
	)			`[static]`

Create a default style NumberFormat for the specified locale.

The default formatting style is locale dependent.

Parameters:

inLocale

the given locale.

NOTE: New users are strongly encouraged to use icu::number::NumberFormatter instead of NumberFormat.

Stable:: ICU 2.0

static NumberFormat* icu::NumberFormat::createInstance ( UErrorCode & ) [static]

Create a default style NumberFormat for the current default locale.

The default formatting style is locale dependent.

NOTE: New users are strongly encouraged to use icu::number::NumberFormatter instead of NumberFormat.

Stable:: ICU 2.0

static NumberFormat* icu::NumberFormat::createPercentInstance	(	const Locale &	inLocale,
		UErrorCode &
	)			`[static]`

Returns a percentage format for the specified locale.

NOTE: New users are strongly encouraged to use icu::number::NumberFormatter instead of NumberFormat.

Parameters:

inLocale

the given locale.

Stable:: ICU 2.0

static NumberFormat* icu::NumberFormat::createPercentInstance ( UErrorCode & ) [static]

Returns a percentage format for the current default locale.

NOTE: New users are strongly encouraged to use icu::number::NumberFormatter instead of NumberFormat.

Stable:: ICU 2.0

static NumberFormat* icu::NumberFormat::createScientificInstance	(	const Locale &	inLocale,
		UErrorCode &
	)			`[static]`

Returns a scientific format for the specified locale.

NOTE: New users are strongly encouraged to use icu::number::NumberFormatter instead of NumberFormat.

Parameters:

inLocale

the given locale.

Stable:: ICU 2.0

static NumberFormat* icu::NumberFormat::createScientificInstance ( UErrorCode & ) [static]

Returns a scientific format for the current default locale.

NOTE: New users are strongly encouraged to use icu::number::NumberFormatter instead of NumberFormat.

Stable:: ICU 2.0

static const SharedNumberFormat* icu::NumberFormat::createSharedInstance	(	const Locale &	inLocale,
		UNumberFormatStyle	style,
		UErrorCode &	status
	)			`[static]`

ICU use only.

Returns handle to the shared, cached NumberFormat instance for given locale. On success, caller must call removeRef() on returned value once it is done with the shared instance.

Internal:: Do not use. This API is for internal use only.

virtual UnicodeString& icu::NumberFormat::format	(	const number::impl::DecimalQuantity &	number,
		UnicodeString &	appendTo,
		FieldPosition &	pos,
		UErrorCode &	status
	)			const `[virtual]`

Format a decimal number.

The number is a DecimalQuantity wrapper onto a floating point decimal number. The default implementation in NumberFormat converts the decimal number to a double and formats that. Subclasses of NumberFormat that want to specifically handle big decimal numbers must override this method. class DecimalFormat does so.

Parameters:

	number	The number, a DecimalQuantity format Decimal Floating Point.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	pos	On input: an alignment field, if desired. On output: the offsets of the alignment field.
	status	Output param filled with success/failure status.

Returns:: Reference to 'appendTo' parameter.

Internal:: Do not use. This API is for internal use only.

Reimplemented in icu::DecimalFormat, and icu::RuleBasedNumberFormat.

virtual UnicodeString& icu::NumberFormat::format	(	const number::impl::DecimalQuantity &	number,
		UnicodeString &	appendTo,
		FieldPositionIterator *	posIter,
		UErrorCode &	status
	)			const `[virtual]`

Format a decimal number.

The number is a DecimalQuantity wrapper onto a floating point decimal number. The default implementation in NumberFormat converts the decimal number to a double and formats that. Subclasses of NumberFormat that want to specifically handle big decimal numbers must override this method. class DecimalFormat does so.

Parameters:

	number	The number, a DecimalQuantity format Decimal Floating Point.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	posIter	On return, can be used to iterate over positions of fields generated by this format call.
	status	Output param filled with success/failure status.

Returns:: Reference to 'appendTo' parameter.

Internal:: Do not use. This API is for internal use only.

Reimplemented in icu::DecimalFormat, and icu::RuleBasedNumberFormat.

virtual UnicodeString& icu::NumberFormat::format	(	StringPiece	number,
		UnicodeString &	appendTo,
		FieldPositionIterator *	posIter,
		UErrorCode &	status
	)			const `[virtual]`

Format a decimal number.

Subclasses must implement this method. The syntax of the unformatted number is a "numeric string" as defined in the Decimal Arithmetic Specification, available at http://speleotrove.com/decimal

Parameters:

	number	The unformatted number, as a string, to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	posIter	On return, can be used to iterate over positions of fields generated by this format call. Can be NULL.
	status	Output param filled with success/failure status.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 4.4

Reimplemented in icu::DecimalFormat.

virtual UnicodeString& icu::NumberFormat::format	(	int64_t	number,
		UnicodeString &	appendTo,
		FieldPositionIterator *	posIter,
		UErrorCode &	status
	)			const `[virtual]`

Format an int64 number.

Subclasses must implement this method.

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	posIter	On return, can be used to iterate over positions of fields generated by this format call. Can be NULL.
	status	Output param filled with success/failure status.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 4.4

Reimplemented in icu::DecimalFormat.

virtual UnicodeString& icu::NumberFormat::format	(	int64_t	number,
		UnicodeString &	appendTo,
		FieldPosition &	pos,
		UErrorCode &	status
	)			const `[virtual]`

Format an int64 number.

(Not abstract to retain compatibility with earlier releases, however subclasses should override this method as it just delegates to format(int32_t number...);

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	pos	On input: an alignment field, if desired. On output: the offsets of the alignment field.
	status	Output param filled with success/failure status.

Returns:: Reference to 'appendTo' parameter.

Internal:: Do not use. This API is for internal use only.

Reimplemented in icu::DecimalFormat.

virtual UnicodeString& icu::NumberFormat::format	(	int64_t	number,
		UnicodeString &	appendTo,
		FieldPosition &	pos
	)			const `[virtual]`

Format an int64 number.

(Not abstract to retain compatibility with earlier releases, however subclasses should override this method as it just delegates to format(int32_t number...);

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	pos	On input: an alignment field, if desired. On output: the offsets of the alignment field.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 2.8

Reimplemented in icu::ChoiceFormat, icu::DecimalFormat, and icu::RuleBasedNumberFormat.

virtual UnicodeString& icu::NumberFormat::format	(	int32_t	number,
		UnicodeString &	appendTo,
		FieldPositionIterator *	posIter,
		UErrorCode &	status
	)			const `[virtual]`

Format an int32 number.

Subclasses must implement this method.

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	posIter	On return, can be used to iterate over positions of fields generated by this format call. Can be NULL.
	status	Output param filled with success/failure status.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 4.4

Reimplemented in icu::DecimalFormat.

virtual UnicodeString& icu::NumberFormat::format	(	int32_t	number,
		UnicodeString &	appendTo,
		FieldPosition &	pos,
		UErrorCode &	status
	)			const `[virtual]`

Format a long number.

Concrete subclasses may override this function to provide status return.

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	pos	On input: an alignment field, if desired. On output: the offsets of the alignment field.
	status	the output status.

Returns:: Reference to 'appendTo' parameter.

Internal:: Do not use. This API is for internal use only.

Reimplemented in icu::DecimalFormat.

virtual UnicodeString& icu::NumberFormat::format	(	int32_t	number,
		UnicodeString &	appendTo,
		FieldPosition &	pos
	)			const `[pure virtual]`

Format a long number.

Concrete subclasses must implement these pure virtual methods.

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	pos	On input: an alignment field, if desired. On output: the offsets of the alignment field.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 2.0

Implemented in icu::ChoiceFormat, icu::DecimalFormat, and icu::RuleBasedNumberFormat.

virtual UnicodeString& icu::NumberFormat::format	(	double	number,
		UnicodeString &	appendTo,
		FieldPositionIterator *	posIter,
		UErrorCode &	status
	)			const `[virtual]`

Format a double number.

Subclasses must implement this method.

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	posIter	On return, can be used to iterate over positions of fields generated by this format call. Can be NULL.
	status	Output param filled with success/failure status.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 4.4

Reimplemented in icu::DecimalFormat.

virtual UnicodeString& icu::NumberFormat::format	(	double	number,
		UnicodeString &	appendTo,
		FieldPosition &	pos,
		UErrorCode &	status
	)			const `[virtual]`

Format a double number.

By default, the parent function simply calls the base class and does not return an error status. Therefore, the status may be ignored in some subclasses.

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	pos	On input: an alignment field, if desired. On output: the offsets of the alignment field.
	status	error status

Returns:: Reference to 'appendTo' parameter.

Internal:: Do not use. This API is for internal use only.

Reimplemented in icu::DecimalFormat.

virtual UnicodeString& icu::NumberFormat::format	(	double	number,
		UnicodeString &	appendTo,
		FieldPosition &	pos
	)			const `[pure virtual]`

Format a double number.

Concrete subclasses must implement these pure virtual methods.

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	pos	On input: an alignment field, if desired. On output: the offsets of the alignment field.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 2.0

Implemented in icu::ChoiceFormat, icu::DecimalFormat, and icu::RuleBasedNumberFormat.

UnicodeString& icu::NumberFormat::format	(	int64_t	number,
		UnicodeString &	appendTo
	)			const

Format an int64 number.

These methods call the NumberFormat pure virtual format() methods with the default FieldPosition.

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 2.8

UnicodeString& icu::NumberFormat::format	(	int32_t	number,
		UnicodeString &	appendTo
	)			const

Format a long number.

These methods call the NumberFormat pure virtual format() methods with the default FieldPosition.

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 2.0

UnicodeString& icu::NumberFormat::format	(	double	number,
		UnicodeString &	appendTo
	)			const

Format a double number.

These methods call the NumberFormat pure virtual format() methods with the default FieldPosition.

Parameters:

	number	The value to be formatted.
	appendTo	Output parameter to receive result. Result is appended to existing contents.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 2.0

virtual UnicodeString& icu::NumberFormat::format	(	const Formattable &	obj,
		UnicodeString &	appendTo,
		FieldPositionIterator *	posIter,
		UErrorCode &	status
	)			const `[virtual]`

Format an object to produce a string.

This method handles Formattable objects with numeric types. If the Formattable object type is not a numeric type, then it returns a failing UErrorCode.

Parameters:

	obj	The object to format.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	posIter	On return, can be used to iterate over positions of fields generated by this format call. Can be NULL.
	status	Output param filled with success/failure status.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 4.4

Reimplemented from icu::Format.

virtual UnicodeString& icu::NumberFormat::format	(	const Formattable &	obj,
		UnicodeString &	appendTo,
		FieldPosition &	pos,
		UErrorCode &	status
	)			const `[virtual]`

Format an object to produce a string.

This method handles Formattable objects with numeric types. If the Formattable object type is not a numeric type, then it returns a failing UErrorCode.

Parameters:

	obj	The object to format.
	appendTo	Output parameter to receive result. Result is appended to existing contents.
	pos	On input: an alignment field, if desired. On output: the offsets of the alignment field.
	status	Output param filled with success/failure status.

Returns:: Reference to 'appendTo' parameter.

Stable:: ICU 2.0

Implements icu::Format.

static StringEnumeration* icu::NumberFormat::getAvailableLocales ( void ) [static]

Return a StringEnumeration over the locales available at the time of the call, including registered locales.

Returns:: a StringEnumeration over the locales available at the time of the call

Stable:: ICU 2.6

static const Locale* icu::NumberFormat::getAvailableLocales ( int32_t & count ) [static]

Get the set of Locales for which NumberFormats are installed.

Parameters:

count

Output param to receive the size of the locales

Stable:: ICU 2.0

virtual UDisplayContext icu::NumberFormat::getContext	(	UDisplayContextType	type,
		UErrorCode &	status
	)			const `[virtual]`

Get the formatter's UDisplayContext value for the specified UDisplayContextType, such as UDISPCTX_TYPE_CAPITALIZATION.

Parameters:

	type	The UDisplayContextType whose value to return
	status	Input/output status. If at entry this indicates a failure status, the function will do nothing; otherwise this will be updated with any new status from the function.

Returns:: The UDisplayContextValue for the specified type.

Stable:: ICU 53

const char16_t* icu::NumberFormat::getCurrency ( ) const

Gets the currency used to display currency amounts.

This may be an empty string for some subclasses.

Returns:: a 3-letter null-terminated ISO code indicating the currency in use, or a pointer to the empty string.

Stable:: ICU 2.6

virtual UClassID icu::NumberFormat::getDynamicClassID ( void ) const [pure virtual]

Returns a unique class ID POLYMORPHICALLY.

Pure virtual override. This method is to implement a simple version of RTTI, since not all C++ compilers support genuine RTTI. Polymorphic operator==() and clone() methods call this method.

Returns:: The class ID for this object. All objects of a given class have the same class ID. Objects of other classes have different class IDs.

Stable:: ICU 2.0

Reimplemented from icu::UObject.

Implemented in icu::ChoiceFormat, icu::CompactDecimalFormat, icu::DecimalFormat, and icu::RuleBasedNumberFormat.

virtual void icu::NumberFormat::getEffectiveCurrency	(	char16_t *	result,
		UErrorCode &	ec
	)			const `[protected, virtual]`

Returns the currency in effect for this formatter.

Subclasses should override this method as needed. Unlike getCurrency(), this method should never return "".

Returns:: output parameter for null-terminated result, which must have a capacity of at least 4

Internal:: Do not use. This API is for internal use only.

int32_t icu::NumberFormat::getMaximumFractionDigits ( void ) const

Returns the maximum number of digits allowed in the fraction portion of a number.

Returns:: the maximum number of digits allowed in the fraction portion of a number.

See also:: setMaximumFractionDigits

Stable:: ICU 2.0

int32_t icu::NumberFormat::getMaximumIntegerDigits ( void ) const

Returns the maximum number of digits allowed in the integer portion of a number.

Returns:: the maximum number of digits allowed in the integer portion of a number.

See also:: setMaximumIntegerDigits

Stable:: ICU 2.0

int32_t icu::NumberFormat::getMinimumFractionDigits ( void ) const

Returns the minimum number of digits allowed in the fraction portion of a number.

Returns:: the minimum number of digits allowed in the fraction portion of a number.

See also:: setMinimumFractionDigits

Stable:: ICU 2.0

int32_t icu::NumberFormat::getMinimumIntegerDigits ( void ) const

Returns the minimum number of digits allowed in the integer portion of a number.

Returns:: the minimum number of digits allowed in the integer portion of a number.

See also:: setMinimumIntegerDigits

Stable:: ICU 2.0

virtual ERoundingMode icu::NumberFormat::getRoundingMode ( void ) const [virtual]

Get the rounding mode.

This will always return NumberFormat::ERoundingMode::kRoundUnnecessary if the subclass does not support rounding.

Returns:: A rounding mode

Stable:: ICU 60

Reimplemented in icu::DecimalFormat, and icu::RuleBasedNumberFormat.

static UClassID icu::NumberFormat::getStaticClassID ( void ) [static]

Return the class ID for this class.

This is useful for comparing to a return value from getDynamicClassID(). Note that, because NumberFormat is an abstract base class, no fully constructed object will have the class ID returned by NumberFormat::getStaticClassID().

Returns:: The class ID for all objects of this class.

Stable:: ICU 2.0

Reimplemented in icu::ChoiceFormat, icu::CompactDecimalFormat, icu::DecimalFormat, and icu::RuleBasedNumberFormat.

static NumberFormat* icu::NumberFormat::internalCreateInstance	(	const Locale &	desiredLocale,
		UNumberFormatStyle	style,
		UErrorCode &	errorCode
	)			`[static]`

ICU use only.

Creates NumberFormat instance without using the cache.

Internal:: Do not use. This API is for internal use only.

UBool icu::NumberFormat::isGroupingUsed ( void ) const

Returns true if grouping is used in this format.

For example, in the English locale, with grouping on, the number 1234567 might be formatted as "1,234,567". The grouping separator as well as the size of each group is locale dependent and is determined by sub-classes of NumberFormat.

See also:: setGroupingUsed

Stable:: ICU 2.0

UBool icu::NumberFormat::isLenient ( void ) const [inline, virtual]

Returns whether lenient parsing is enabled (it is off by default).

Returns:: TRUE if lenient parsing is enabled, FALSE otherwise.

See also:: setLenient

Stable:: ICU 4.8

Reimplemented in icu::RuleBasedNumberFormat.

Definition at line 1243 of file numfmt.h.

UBool icu::NumberFormat::isParseIntegerOnly ( void ) const [inline]

Return true if this format will parse numbers as integers only.

For example in the English locale, with ParseIntegerOnly true, the string "1234." would be parsed as the integer value 1234 and parsing would stop at the "." character. Of course, the exact format accepted by the parse operation is locale dependant and determined by sub-classes of NumberFormat.

Returns:: true if this format will parse numbers as integers only.

Stable:: ICU 2.0

Definition at line 1237 of file numfmt.h.

static NumberFormat* icu::NumberFormat::makeInstance	(	const Locale &	desiredLocale,
		UNumberFormatStyle	style,
		UBool	mustBeDecimalFormat,
		UErrorCode &	errorCode
	)			`[static, protected]`

Creates the specified number format style of the desired locale.

If mustBeDecimalFormat is TRUE, then the returned pointer is either a DecimalFormat or it is NULL.

Internal:: Do not use. This API is for internal use only.

NumberFormat& icu::NumberFormat::operator= ( const NumberFormat & ) [protected]

Assignment operator.

Stable:: ICU 2.0

Reimplemented from icu::Format.

Reimplemented in icu::ChoiceFormat, icu::CompactDecimalFormat, icu::DecimalFormat, and icu::RuleBasedNumberFormat.

virtual UBool icu::NumberFormat::operator== ( const Format & other ) const [virtual]

Return true if the given Format objects are semantically equal.

Objects of different subclasses are considered unequal.

Returns:: true if the given Format objects are semantically equal.

Stable:: ICU 2.0

Reimplemented in icu::ChoiceFormat, icu::DecimalFormat, and icu::RuleBasedNumberFormat.

virtual void icu::NumberFormat::parse	(	const UnicodeString &	text,
		Formattable &	result,
		UErrorCode &	status
	)			const `[virtual]`

Parse a string as a numeric value, and return a Formattable numeric object.

This method parses integers only if IntegerOnly is set.

Parameters:

	text	The text to be parsed.
	result	Formattable to be set to the parse result. If parse fails, return contents are undefined.
	status	Output parameter set to a failure error code when a failure occurs.

See also:: NumberFormat::isParseIntegerOnly

Stable:: ICU 2.0

Reimplemented in icu::CompactDecimalFormat.

virtual void icu::NumberFormat::parse	(	const UnicodeString &	text,
		Formattable &	result,
		ParsePosition &	parsePosition
	)			const `[pure virtual]`

Return a long if possible (e.g.

within range LONG_MAX, LONG_MAX], and with no decimals), otherwise a double. If IntegerOnly is set, will stop at a decimal point (or equivalent; e.g. for rational numbers "1 2/3", will stop after the 1).

If no object can be parsed, index is unchanged, and NULL is returned.

This is a pure virtual which concrete subclasses must implement.

Parameters:

	text	The text to be parsed.
	result	Formattable to be set to the parse result. If parse fails, return contents are undefined.
	parsePosition	The position to start parsing at on input. On output, moved to after the last successfully parse character. On parse failure, does not change.

Stable:: ICU 2.0

Implemented in icu::ChoiceFormat, icu::CompactDecimalFormat, icu::DecimalFormat, and icu::RuleBasedNumberFormat.

virtual CurrencyAmount* icu::NumberFormat::parseCurrency	(	const UnicodeString &	text,
		ParsePosition &	pos
	)			const `[virtual]`

Parses text from the given string as a currency amount.

Unlike the parse() method, this method will attempt to parse a generic currency name, searching for a match of this object's locale's currency display names, or for a 3-letter ISO currency code. This method will fail if this format is not a currency format, that is, if it does not contain the currency pattern symbol (U+00A4) in its prefix or suffix.

Parameters:

	text	the string to parse
	pos	input-output position; on input, the position within text to match; must have 0 <= pos.getIndex() < text.length(); on output, the position after the last matched character. If the parse fails, the position in unchanged upon output.

Returns:: if parse succeeds, a pointer to a newly-created CurrencyAmount object (owned by the caller) containing information about the parsed currency; if parse fails, this is NULL.

Stable:: ICU 49

Reimplemented in icu::CompactDecimalFormat, and icu::DecimalFormat.

virtual void icu::NumberFormat::parseObject	(	const UnicodeString &	source,
		Formattable &	result,
		ParsePosition &	parse_pos
	)			const `[virtual]`

Parse a string to produce an object.

This methods handles parsing of numeric strings into Formattable objects with numeric types.

Before calling, set parse_pos.index to the offset you want to start parsing at in the source. After calling, parse_pos.index indicates the position after the successfully parsed text. If an error occurs, parse_pos.index is unchanged.

When parsing, leading whitespace is discarded (with successful parse), while trailing whitespace is left as is.

See Format::parseObject() for more.

Parameters:

	source	The string to be parsed into an object.
	result	Formattable to be set to the parse result. If parse fails, return contents are undefined.
	parse_pos	The position to start parsing at. Upon return this param is set to the position after the last character successfully parsed. If the source is not parsed successfully, this param will remain unchanged.

Returns:: A newly created Formattable* object, or NULL on failure. The caller owns this and should delete it when done.

Stable:: ICU 2.0

Implements icu::Format.

static URegistryKey icu::NumberFormat::registerFactory	(	NumberFormatFactory *	toAdopt,
		UErrorCode &	status
	)			`[static]`

Register a new NumberFormatFactory.

The factory will be adopted. Because ICU may choose to cache NumberFormat objects internally, this must be called at application startup, prior to any calls to NumberFormat::createInstance to avoid undefined behavior.

Parameters:

	toAdopt	the NumberFormatFactory instance to be adopted
	status	the in/out status code, no special meanings are assigned

Returns:: a registry key that can be used to unregister this factory

Stable:: ICU 2.6

virtual void icu::NumberFormat::setContext	(	UDisplayContext	value,
		UErrorCode &	status
	)			`[virtual]`

Set a particular UDisplayContext value in the formatter, such as UDISPCTX_CAPITALIZATION_FOR_STANDALONE.

Parameters:

	value	The UDisplayContext value to set.
	status	Input/output status. If at entry this indicates a failure status, the function will do nothing; otherwise this will be updated with any new status from the function.

Stable:: ICU 53

Reimplemented in icu::RuleBasedNumberFormat.

virtual void icu::NumberFormat::setCurrency	(	const char16_t *	theCurrency,
		UErrorCode &	ec
	)			`[virtual]`

Sets the currency used to display currency amounts.

This takes effect immediately, if this format is a currency format. If this format is not a currency format, then the currency is used if and when this object becomes a currency format.

Parameters:

	theCurrency	a 3-letter ISO code indicating new currency to use. It need not be null-terminated. May be the empty string or NULL to indicate no currency.
	ec	input-output error code

Stable:: ICU 3.0

Reimplemented in icu::DecimalFormat.

virtual void icu::NumberFormat::setGroupingUsed ( UBool newValue ) [virtual]

Set whether or not grouping will be used in this format.

Parameters:

newValue

True, grouping will be used in this format.

See also:: getGroupingUsed

Stable:: ICU 2.0

Reimplemented in icu::DecimalFormat.

virtual void icu::NumberFormat::setLenient ( UBool enable ) [virtual]

Sets whether lenient parsing should be enabled (it is off by default).

Parameters:

enable TRUE if lenient parsing should be used, FALSE otherwise.

Stable:: ICU 4.8

Reimplemented in icu::DecimalFormat, and icu::RuleBasedNumberFormat.

virtual void icu::NumberFormat::setMaximumFractionDigits ( int32_t newValue ) [virtual]

Sets the maximum number of digits allowed in the fraction portion of a number.

maximumFractionDigits must be >= minimumFractionDigits. If the new value for maximumFractionDigits is less than the current value of minimumFractionDigits, then minimumFractionDigits will also be set to the new value.

Parameters:

newValue

the new value to be set.

See also:: getMaximumFractionDigits

Stable:: ICU 2.0

Reimplemented in icu::DecimalFormat.

virtual void icu::NumberFormat::setMaximumIntegerDigits ( int32_t newValue ) [virtual]

Sets the maximum number of digits allowed in the integer portion of a number.

maximumIntegerDigits must be >= minimumIntegerDigits. If the new value for maximumIntegerDigits is less than the current value of minimumIntegerDigits, then minimumIntegerDigits will also be set to the new value.

Parameters:

newValue

the new value for the maximum number of digits allowed in the integer portion of a number.

See also:: getMaximumIntegerDigits

Stable:: ICU 2.0

Reimplemented in icu::DecimalFormat.

virtual void icu::NumberFormat::setMinimumFractionDigits ( int32_t newValue ) [virtual]

Sets the minimum number of digits allowed in the fraction portion of a number.

minimumFractionDigits must be <= maximumFractionDigits. If the new value for minimumFractionDigits exceeds the current value of maximumFractionDigits, then maximumIntegerDigits will also be set to the new value

Parameters:

newValue

the new value to be set.

See also:: getMinimumFractionDigits

Stable:: ICU 2.0

Reimplemented in icu::DecimalFormat.

virtual void icu::NumberFormat::setMinimumIntegerDigits ( int32_t newValue ) [virtual]

Sets the minimum number of digits allowed in the integer portion of a number.

minimumIntegerDigits must be <= maximumIntegerDigits. If the new value for minimumIntegerDigits exceeds the current value of maximumIntegerDigits, then maximumIntegerDigits will also be set to the new value.

Parameters:

newValue

the new value to be set.

See also:: getMinimumIntegerDigits

Stable:: ICU 2.0

Reimplemented in icu::DecimalFormat.

virtual void icu::NumberFormat::setParseIntegerOnly ( UBool value ) [virtual]

Sets whether or not numbers should be parsed as integers only.

Parameters:

value

set True, this format will parse numbers as integers only.

See also:: isParseIntegerOnly

Stable:: ICU 2.0

Reimplemented in icu::DecimalFormat.

virtual void icu::NumberFormat::setRoundingMode ( ERoundingMode roundingMode ) [virtual]

Set the rounding mode.

If a subclass does not support rounding, this will do nothing.

Parameters:

roundingMode

A rounding mode

Stable:: ICU 60

Reimplemented in icu::DecimalFormat.

static UBool icu::NumberFormat::unregister	(	URegistryKey	key,
		UErrorCode &	status
	)			`[static]`

Unregister a previously-registered NumberFormatFactory using the key returned from the register call.

Key becomes invalid after a successful call and should not be used again. The NumberFormatFactory corresponding to the key will be deleted. Because ICU may choose to cache NumberFormat objects internally, this should be called during application shutdown, after all calls to NumberFormat::createInstance to avoid undefined behavior.

Parameters:

	key	the registry key returned by a previous call to registerFactory
	status	the in/out status code, no special meanings are assigned

Returns:: TRUE if the factory for the key was successfully unregistered

Stable:: ICU 2.6

Field Documentation

const int32_t icu::NumberFormat::gDefaultMaxIntegerDigits [static, protected]

Internal:: Do not use. This API is for internal use only.

Definition at line 1132 of file numfmt.h.

const int32_t icu::NumberFormat::gDefaultMinIntegerDigits [static, protected]

Internal:: Do not use. This API is for internal use only.

Definition at line 1134 of file numfmt.h.

The documentation for this class was generated from the following file:

numfmt.h

icu::NumberFormat Class Reference

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Static Protected Attributes

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Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

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