/
decimfmt.h
1901 lines (1771 loc) · 75.3 KB
/
decimfmt.h
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/*
********************************************************************************
* Copyright (C) 1997-2009, International Business Machines
* Corporation and others. All Rights Reserved.
********************************************************************************
*
* File DECIMFMT.H
*
* Modification History:
*
* Date Name Description
* 02/19/97 aliu Converted from java.
* 03/20/97 clhuang Updated per C++ implementation.
* 04/03/97 aliu Rewrote parsing and formatting completely, and
* cleaned up and debugged. Actually works now.
* 04/17/97 aliu Changed DigitCount to int per code review.
* 07/10/97 helena Made ParsePosition a class and get rid of the function
* hiding problems.
* 09/09/97 aliu Ported over support for exponential formats.
* 07/20/98 stephen Changed documentation
********************************************************************************
*/
#ifndef DECIMFMT_H
#define DECIMFMT_H
#include "unicode/utypes.h"
/**
* \file
* \brief C++ API: Formats decimal numbers.
*/
#if !UCONFIG_NO_FORMATTING
#include "unicode/dcfmtsym.h"
#include "unicode/numfmt.h"
#include "unicode/locid.h"
U_NAMESPACE_BEGIN
class DigitList;
class ChoiceFormat;
class UnicodeSet;
/**
* DecimalFormat is a concrete subclass of NumberFormat that formats decimal
* numbers. It has a variety of features designed to make it possible to parse
* and format numbers in any locale, including support for Western, Arabic, or
* Indic digits. It also supports different flavors of numbers, including
* integers ("123"), fixed-point numbers ("123.4"), scientific notation
* ("1.23E4"), percentages ("12%"), and currency amounts ("$123"). All of these
* flavors can be easily localized.
*
* <p>To obtain a NumberFormat for a specific locale (including the default
* locale) call one of NumberFormat's factory methods such as
* createInstance(). Do not call the DecimalFormat constructors directly, unless
* you know what you are doing, since the NumberFormat factory methods may
* return subclasses other than DecimalFormat.
*
* <p><strong>Example Usage</strong>
*
* \code
* // Normally we would have a GUI with a menu for this
* int32_t locCount;
* const Locale* locales = NumberFormat::getAvailableLocales(locCount);
*
* double myNumber = -1234.56;
* UErrorCode success = U_ZERO_ERROR;
* NumberFormat* form;
*
* // Print out a number with the localized number, currency and percent
* // format for each locale.
* UnicodeString countryName;
* UnicodeString displayName;
* UnicodeString str;
* UnicodeString pattern;
* Formattable fmtable;
* for (int32_t j = 0; j < 3; ++j) {
* cout << endl << "FORMAT " << j << endl;
* for (int32_t i = 0; i < locCount; ++i) {
* if (locales[i].getCountry(countryName).size() == 0) {
* // skip language-only
* continue;
* }
* switch (j) {
* case 0:
* form = NumberFormat::createInstance(locales[i], success ); break;
* case 1:
* form = NumberFormat::createCurrencyInstance(locales[i], success ); break;
* default:
* form = NumberFormat::createPercentInstance(locales[i], success ); break;
* }
* if (form) {
* str.remove();
* pattern = ((DecimalFormat*)form)->toPattern(pattern);
* cout << locales[i].getDisplayName(displayName) << ": " << pattern;
* cout << " -> " << form->format(myNumber,str) << endl;
* form->parse(form->format(myNumber,str), fmtable, success);
* delete form;
* }
* }
* }
* \endcode
*
* <p><strong>Patterns</strong>
*
* <p>A DecimalFormat consists of a <em>pattern</em> and a set of
* <em>symbols</em>. The pattern may be set directly using
* applyPattern(), or indirectly using other API methods which
* manipulate aspects of the pattern, such as the minimum number of integer
* digits. The symbols are stored in a DecimalFormatSymbols
* object. When using the NumberFormat factory methods, the
* pattern and symbols are read from ICU's locale data.
*
* <p><strong>Special Pattern Characters</strong>
*
* <p>Many characters in a pattern are taken literally; they are matched during
* parsing and output unchanged during formatting. Special characters, on the
* other hand, stand for other characters, strings, or classes of characters.
* For example, the '#' character is replaced by a localized digit. Often the
* replacement character is the same as the pattern character; in the U.S. locale,
* the ',' grouping character is replaced by ','. However, the replacement is
* still happening, and if the symbols are modified, the grouping character
* changes. Some special characters affect the behavior of the formatter by
* their presence; for example, if the percent character is seen, then the
* value is multiplied by 100 before being displayed.
*
* <p>To insert a special character in a pattern as a literal, that is, without
* any special meaning, the character must be quoted. There are some exceptions to
* this which are noted below.
*
* <p>The characters listed here are used in non-localized patterns. Localized
* patterns use the corresponding characters taken from this formatter's
* DecimalFormatSymbols object instead, and these characters lose
* their special status. Two exceptions are the currency sign and quote, which
* are not localized.
*
* <table border=0 cellspacing=3 cellpadding=0>
* <tr bgcolor="#ccccff">
* <td align=left><strong>Symbol</strong>
* <td align=left><strong>Location</strong>
* <td align=left><strong>Localized?</strong>
* <td align=left><strong>Meaning</strong>
* <tr valign=top>
* <td><code>0</code>
* <td>Number
* <td>Yes
* <td>Digit
* <tr valign=top bgcolor="#eeeeff">
* <td><code>1-9</code>
* <td>Number
* <td>Yes
* <td>'1' through '9' indicate rounding.
* <tr valign=top>
* <td><code>\htmlonly@\endhtmlonly</code> <!--doxygen doesn't like @-->
* <td>Number
* <td>No
* <td>Significant digit
* <tr valign=top bgcolor="#eeeeff">
* <td><code>#</code>
* <td>Number
* <td>Yes
* <td>Digit, zero shows as absent
* <tr valign=top>
* <td><code>.</code>
* <td>Number
* <td>Yes
* <td>Decimal separator or monetary decimal separator
* <tr valign=top bgcolor="#eeeeff">
* <td><code>-</code>
* <td>Number
* <td>Yes
* <td>Minus sign
* <tr valign=top>
* <td><code>,</code>
* <td>Number
* <td>Yes
* <td>Grouping separator
* <tr valign=top bgcolor="#eeeeff">
* <td><code>E</code>
* <td>Number
* <td>Yes
* <td>Separates mantissa and exponent in scientific notation.
* <em>Need not be quoted in prefix or suffix.</em>
* <tr valign=top>
* <td><code>+</code>
* <td>Exponent
* <td>Yes
* <td>Prefix positive exponents with localized plus sign.
* <em>Need not be quoted in prefix or suffix.</em>
* <tr valign=top bgcolor="#eeeeff">
* <td><code>;</code>
* <td>Subpattern boundary
* <td>Yes
* <td>Separates positive and negative subpatterns
* <tr valign=top>
* <td><code>\%</code>
* <td>Prefix or suffix
* <td>Yes
* <td>Multiply by 100 and show as percentage
* <tr valign=top bgcolor="#eeeeff">
* <td><code>\\u2030</code>
* <td>Prefix or suffix
* <td>Yes
* <td>Multiply by 1000 and show as per mille
* <tr valign=top>
* <td><code>\htmlonly¤\endhtmlonly</code> (<code>\\u00A4</code>)
* <td>Prefix or suffix
* <td>No
* <td>Currency sign, replaced by currency symbol. If
* doubled, replaced by international currency symbol.
* If present in a pattern, the monetary decimal separator
* is used instead of the decimal separator.
* <tr valign=top bgcolor="#eeeeff">
* <td><code>'</code>
* <td>Prefix or suffix
* <td>No
* <td>Used to quote special characters in a prefix or suffix,
* for example, <code>"'#'#"</code> formats 123 to
* <code>"#123"</code>. To create a single quote
* itself, use two in a row: <code>"# o''clock"</code>.
* <tr valign=top>
* <td><code>*</code>
* <td>Prefix or suffix boundary
* <td>Yes
* <td>Pad escape, precedes pad character
* </table>
*
* <p>A DecimalFormat pattern contains a postive and negative
* subpattern, for example, "#,##0.00;(#,##0.00)". Each subpattern has a
* prefix, a numeric part, and a suffix. If there is no explicit negative
* subpattern, the negative subpattern is the localized minus sign prefixed to the
* positive subpattern. That is, "0.00" alone is equivalent to "0.00;-0.00". If there
* is an explicit negative subpattern, it serves only to specify the negative
* prefix and suffix; the number of digits, minimal digits, and other
* characteristics are ignored in the negative subpattern. That means that
* "#,##0.0#;(#)" has precisely the same result as "#,##0.0#;(#,##0.0#)".
*
* <p>The prefixes, suffixes, and various symbols used for infinity, digits,
* thousands separators, decimal separators, etc. may be set to arbitrary
* values, and they will appear properly during formatting. However, care must
* be taken that the symbols and strings do not conflict, or parsing will be
* unreliable. For example, either the positive and negative prefixes or the
* suffixes must be distinct for parse() to be able
* to distinguish positive from negative values. Another example is that the
* decimal separator and thousands separator should be distinct characters, or
* parsing will be impossible.
*
* <p>The <em>grouping separator</em> is a character that separates clusters of
* integer digits to make large numbers more legible. It commonly used for
* thousands, but in some locales it separates ten-thousands. The <em>grouping
* size</em> is the number of digits between the grouping separators, such as 3
* for "100,000,000" or 4 for "1 0000 0000". There are actually two different
* grouping sizes: One used for the least significant integer digits, the
* <em>primary grouping size</em>, and one used for all others, the
* <em>secondary grouping size</em>. In most locales these are the same, but
* sometimes they are different. For example, if the primary grouping interval
* is 3, and the secondary is 2, then this corresponds to the pattern
* "#,##,##0", and the number 123456789 is formatted as "12,34,56,789". If a
* pattern contains multiple grouping separators, the interval between the last
* one and the end of the integer defines the primary grouping size, and the
* interval between the last two defines the secondary grouping size. All others
* are ignored, so "#,##,###,####" == "###,###,####" == "##,#,###,####".
*
* <p>Illegal patterns, such as "#.#.#" or "#.###,###", will cause
* DecimalFormat to set a failing UErrorCode.
*
* <p><strong>Pattern BNF</strong>
*
* <pre>
* pattern := subpattern (';' subpattern)?
* subpattern := prefix? number exponent? suffix?
* number := (integer ('.' fraction)?) | sigDigits
* prefix := '\\u0000'..'\\uFFFD' - specialCharacters
* suffix := '\\u0000'..'\\uFFFD' - specialCharacters
* integer := '#'* '0'* '0'
* fraction := '0'* '#'*
* sigDigits := '#'* '@' '@'* '#'*
* exponent := 'E' '+'? '0'* '0'
* padSpec := '*' padChar
* padChar := '\\u0000'..'\\uFFFD' - quote
*
* Notation:
* X* 0 or more instances of X
* X? 0 or 1 instances of X
* X|Y either X or Y
* C..D any character from C up to D, inclusive
* S-T characters in S, except those in T
* </pre>
* The first subpattern is for positive numbers. The second (optional)
* subpattern is for negative numbers.
*
* <p>Not indicated in the BNF syntax above:
*
* <ul><li>The grouping separator ',' can occur inside the integer and
* sigDigits elements, between any two pattern characters of that
* element, as long as the integer or sigDigits element is not
* followed by the exponent element.
*
* <li>Two grouping intervals are recognized: That between the
* decimal point and the first grouping symbol, and that
* between the first and second grouping symbols. These
* intervals are identical in most locales, but in some
* locales they differ. For example, the pattern
* "#,##,###" formats the number 123456789 as
* "12,34,56,789".</li>
*
* <li>The pad specifier <code>padSpec</code> may appear before the prefix,
* after the prefix, before the suffix, after the suffix, or not at all.
*
* <li>In place of '0', the digits '1' through '9' may be used to
* indicate a rounding increment.
* </ul>
*
* <p><strong>Parsing</strong>
*
* <p>DecimalFormat parses all Unicode characters that represent
* decimal digits, as defined by u_charDigitValue(). In addition,
* DecimalFormat also recognizes as digits the ten consecutive
* characters starting with the localized zero digit defined in the
* DecimalFormatSymbols object. During formatting, the
* DecimalFormatSymbols-based digits are output.
*
* <p>During parsing, grouping separators are ignored.
*
* <p>If parse(UnicodeString&,Formattable&,ParsePosition&)
* fails to parse a string, it leaves the parse position unchanged.
* The convenience method parse(UnicodeString&,Formattable&,UErrorCode&)
* indicates parse failure by setting a failing
* UErrorCode.
*
* <p><strong>Formatting</strong>
*
* <p>Formatting is guided by several parameters, all of which can be
* specified either using a pattern or using the API. The following
* description applies to formats that do not use <a href="#sci">scientific
* notation</a> or <a href="#sigdig">significant digits</a>.
*
* <ul><li>If the number of actual integer digits exceeds the
* <em>maximum integer digits</em>, then only the least significant
* digits are shown. For example, 1997 is formatted as "97" if the
* maximum integer digits is set to 2.
*
* <li>If the number of actual integer digits is less than the
* <em>minimum integer digits</em>, then leading zeros are added. For
* example, 1997 is formatted as "01997" if the minimum integer digits
* is set to 5.
*
* <li>If the number of actual fraction digits exceeds the <em>maximum
* fraction digits</em>, then half-even rounding it performed to the
* maximum fraction digits. For example, 0.125 is formatted as "0.12"
* if the maximum fraction digits is 2. This behavior can be changed
* by specifying a rounding increment and a rounding mode.
*
* <li>If the number of actual fraction digits is less than the
* <em>minimum fraction digits</em>, then trailing zeros are added.
* For example, 0.125 is formatted as "0.1250" if the mimimum fraction
* digits is set to 4.
*
* <li>Trailing fractional zeros are not displayed if they occur
* <em>j</em> positions after the decimal, where <em>j</em> is less
* than the maximum fraction digits. For example, 0.10004 is
* formatted as "0.1" if the maximum fraction digits is four or less.
* </ul>
*
* <p><strong>Special Values</strong>
*
* <p><code>NaN</code> is represented as a single character, typically
* <code>\\uFFFD</code>. This character is determined by the
* DecimalFormatSymbols object. This is the only value for which
* the prefixes and suffixes are not used.
*
* <p>Infinity is represented as a single character, typically
* <code>\\u221E</code>, with the positive or negative prefixes and suffixes
* applied. The infinity character is determined by the
* DecimalFormatSymbols object.
*
* <a name="sci"><strong>Scientific Notation</strong></a>
*
* <p>Numbers in scientific notation are expressed as the product of a mantissa
* and a power of ten, for example, 1234 can be expressed as 1.234 x 10<sup>3</sup>. The
* mantissa is typically in the half-open interval [1.0, 10.0) or sometimes [0.0, 1.0),
* but it need not be. DecimalFormat supports arbitrary mantissas.
* DecimalFormat can be instructed to use scientific
* notation through the API or through the pattern. In a pattern, the exponent
* character immediately followed by one or more digit characters indicates
* scientific notation. Example: "0.###E0" formats the number 1234 as
* "1.234E3".
*
* <ul>
* <li>The number of digit characters after the exponent character gives the
* minimum exponent digit count. There is no maximum. Negative exponents are
* formatted using the localized minus sign, <em>not</em> the prefix and suffix
* from the pattern. This allows patterns such as "0.###E0 m/s". To prefix
* positive exponents with a localized plus sign, specify '+' between the
* exponent and the digits: "0.###E+0" will produce formats "1E+1", "1E+0",
* "1E-1", etc. (In localized patterns, use the localized plus sign rather than
* '+'.)
*
* <li>The minimum number of integer digits is achieved by adjusting the
* exponent. Example: 0.00123 formatted with "00.###E0" yields "12.3E-4". This
* only happens if there is no maximum number of integer digits. If there is a
* maximum, then the minimum number of integer digits is fixed at one.
*
* <li>The maximum number of integer digits, if present, specifies the exponent
* grouping. The most common use of this is to generate <em>engineering
* notation</em>, in which the exponent is a multiple of three, e.g.,
* "##0.###E0". The number 12345 is formatted using "##0.####E0" as "12.345E3".
*
* <li>When using scientific notation, the formatter controls the
* digit counts using significant digits logic. The maximum number of
* significant digits limits the total number of integer and fraction
* digits that will be shown in the mantissa; it does not affect
* parsing. For example, 12345 formatted with "##0.##E0" is "12.3E3".
* See the section on significant digits for more details.
*
* <li>The number of significant digits shown is determined as
* follows: If areSignificantDigitsUsed() returns false, then the
* minimum number of significant digits shown is one, and the maximum
* number of significant digits shown is the sum of the <em>minimum
* integer</em> and <em>maximum fraction</em> digits, and is
* unaffected by the maximum integer digits. If this sum is zero,
* then all significant digits are shown. If
* areSignificantDigitsUsed() returns true, then the significant digit
* counts are specified by getMinimumSignificantDigits() and
* getMaximumSignificantDigits(). In this case, the number of
* integer digits is fixed at one, and there is no exponent grouping.
*
* <li>Exponential patterns may not contain grouping separators.
* </ul>
*
* <a name="sigdig"><strong>Significant Digits</strong></a>
*
* <code>DecimalFormat</code> has two ways of controlling how many
* digits are shows: (a) significant digits counts, or (b) integer and
* fraction digit counts. Integer and fraction digit counts are
* described above. When a formatter is using significant digits
* counts, the number of integer and fraction digits is not specified
* directly, and the formatter settings for these counts are ignored.
* Instead, the formatter uses however many integer and fraction
* digits are required to display the specified number of significant
* digits. Examples:
*
* <table border=0 cellspacing=3 cellpadding=0>
* <tr bgcolor="#ccccff">
* <td align=left>Pattern
* <td align=left>Minimum significant digits
* <td align=left>Maximum significant digits
* <td align=left>Number
* <td align=left>Output of format()
* <tr valign=top>
* <td><code>\@\@\@</code>
* <td>3
* <td>3
* <td>12345
* <td><code>12300</code>
* <tr valign=top bgcolor="#eeeeff">
* <td><code>\@\@\@</code>
* <td>3
* <td>3
* <td>0.12345
* <td><code>0.123</code>
* <tr valign=top>
* <td><code>\@\@##</code>
* <td>2
* <td>4
* <td>3.14159
* <td><code>3.142</code>
* <tr valign=top bgcolor="#eeeeff">
* <td><code>\@\@##</code>
* <td>2
* <td>4
* <td>1.23004
* <td><code>1.23</code>
* </table>
*
* <ul>
* <li>Significant digit counts may be expressed using patterns that
* specify a minimum and maximum number of significant digits. These
* are indicated by the <code>'@'</code> and <code>'#'</code>
* characters. The minimum number of significant digits is the number
* of <code>'@'</code> characters. The maximum number of significant
* digits is the number of <code>'@'</code> characters plus the number
* of <code>'#'</code> characters following on the right. For
* example, the pattern <code>"@@@"</code> indicates exactly 3
* significant digits. The pattern <code>"@##"</code> indicates from
* 1 to 3 significant digits. Trailing zero digits to the right of
* the decimal separator are suppressed after the minimum number of
* significant digits have been shown. For example, the pattern
* <code>"@##"</code> formats the number 0.1203 as
* <code>"0.12"</code>.
*
* <li>If a pattern uses significant digits, it may not contain a
* decimal separator, nor the <code>'0'</code> pattern character.
* Patterns such as <code>"@00"</code> or <code>"@.###"</code> are
* disallowed.
*
* <li>Any number of <code>'#'</code> characters may be prepended to
* the left of the leftmost <code>'@'</code> character. These have no
* effect on the minimum and maximum significant digits counts, but
* may be used to position grouping separators. For example,
* <code>"#,#@#"</code> indicates a minimum of one significant digits,
* a maximum of two significant digits, and a grouping size of three.
*
* <li>In order to enable significant digits formatting, use a pattern
* containing the <code>'@'</code> pattern character. Alternatively,
* call setSignificantDigitsUsed(TRUE).
*
* <li>In order to disable significant digits formatting, use a
* pattern that does not contain the <code>'@'</code> pattern
* character. Alternatively, call setSignificantDigitsUsed(FALSE).
*
* <li>The number of significant digits has no effect on parsing.
*
* <li>Significant digits may be used together with exponential notation. Such
* patterns are equivalent to a normal exponential pattern with a minimum and
* maximum integer digit count of one, a minimum fraction digit count of
* <code>getMinimumSignificantDigits() - 1</code>, and a maximum fraction digit
* count of <code>getMaximumSignificantDigits() - 1</code>. For example, the
* pattern <code>"@@###E0"</code> is equivalent to <code>"0.0###E0"</code>.
*
* <li>If signficant digits are in use, then the integer and fraction
* digit counts, as set via the API, are ignored. If significant
* digits are not in use, then the signficant digit counts, as set via
* the API, are ignored.
*
* </ul>
*
* <p><strong>Padding</strong>
*
* <p>DecimalFormat supports padding the result of
* format() to a specific width. Padding may be specified either
* through the API or through the pattern syntax. In a pattern the pad escape
* character, followed by a single pad character, causes padding to be parsed
* and formatted. The pad escape character is '*' in unlocalized patterns, and
* can be localized using DecimalFormatSymbols::setSymbol() with a
* DecimalFormatSymbols::kPadEscapeSymbol
* selector. For example, <code>"$*x#,##0.00"</code> formats 123 to
* <code>"$xx123.00"</code>, and 1234 to <code>"$1,234.00"</code>.
*
* <ul>
* <li>When padding is in effect, the width of the positive subpattern,
* including prefix and suffix, determines the format width. For example, in
* the pattern <code>"* #0 o''clock"</code>, the format width is 10.
*
* <li>The width is counted in 16-bit code units (UChars).
*
* <li>Some parameters which usually do not matter have meaning when padding is
* used, because the pattern width is significant with padding. In the pattern
* "* ##,##,#,##0.##", the format width is 14. The initial characters "##,##,"
* do not affect the grouping size or maximum integer digits, but they do affect
* the format width.
*
* <li>Padding may be inserted at one of four locations: before the prefix,
* after the prefix, before the suffix, or after the suffix. If padding is
* specified in any other location, applyPattern()
* sets a failing UErrorCode. If there is no prefix,
* before the prefix and after the prefix are equivalent, likewise for the
* suffix.
*
* <li>When specified in a pattern, the 32-bit code point immediately
* following the pad escape is the pad character. This may be any character,
* including a special pattern character. That is, the pad escape
* <em>escapes</em> the following character. If there is no character after
* the pad escape, then the pattern is illegal.
*
* </ul>
*
* <p><strong>Rounding</strong>
*
* <p>DecimalFormat supports rounding to a specific increment. For
* example, 1230 rounded to the nearest 50 is 1250. 1.234 rounded to the
* nearest 0.65 is 1.3. The rounding increment may be specified through the API
* or in a pattern. To specify a rounding increment in a pattern, include the
* increment in the pattern itself. "#,#50" specifies a rounding increment of
* 50. "#,##0.05" specifies a rounding increment of 0.05.
*
* <ul>
* <li>Rounding only affects the string produced by formatting. It does
* not affect parsing or change any numerical values.
*
* <li>A <em>rounding mode</em> determines how values are rounded; see
* DecimalFormat::ERoundingMode. Rounding increments specified in
* patterns use the default mode, DecimalFormat::kRoundHalfEven.
*
* <li>Some locales use rounding in their currency formats to reflect the
* smallest currency denomination.
*
* <li>In a pattern, digits '1' through '9' specify rounding, but otherwise
* behave identically to digit '0'.
* </ul>
*
* <p><strong>Synchronization</strong>
*
* <p>DecimalFormat objects are not synchronized. Multiple
* threads should not access one formatter concurrently.
*
* <p><strong>Subclassing</strong>
*
* <p><em>User subclasses are not supported.</em> While clients may write
* subclasses, such code will not necessarily work and will not be
* guaranteed to work stably from release to release.
*/
class U_I18N_API DecimalFormat: public NumberFormat {
public:
/**
* Rounding mode.
* @stable ICU 2.4
*/
enum ERoundingMode {
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 */
// We don't support ROUND_UNNECESSARY
};
/**
* Pad position.
* @stable ICU 2.4
*/
enum EPadPosition {
kPadBeforePrefix,
kPadAfterPrefix,
kPadBeforeSuffix,
kPadAfterSuffix
};
/**
* Create a DecimalFormat using the default pattern and symbols
* for the default locale. This is a convenient way to obtain a
* DecimalFormat when internationalization is not the main concern.
* <P>
* To obtain standard formats for a given locale, use the factory methods
* on NumberFormat such as createInstance. These factories will
* return the most appropriate sub-class of NumberFormat for a given
* locale.
* @param status Output param set to success/failure code. If the
* pattern is invalid this will be set to a failure code.
* @stable ICU 2.0
*/
DecimalFormat(UErrorCode& status);
/**
* Create a DecimalFormat from the given pattern and the symbols
* for the default locale. This is a convenient way to obtain a
* DecimalFormat when internationalization is not the main concern.
* <P>
* To obtain standard formats for a given locale, use the factory methods
* on NumberFormat such as createInstance. These factories will
* return the most appropriate sub-class of NumberFormat for a given
* locale.
* @param pattern A non-localized pattern string.
* @param status Output param set to success/failure code. If the
* pattern is invalid this will be set to a failure code.
* @stable ICU 2.0
*/
DecimalFormat(const UnicodeString& pattern,
UErrorCode& status);
/**
* Create a DecimalFormat from the given pattern and symbols.
* Use this constructor when you need to completely customize the
* behavior of the format.
* <P>
* To obtain standard formats for a given
* locale, use the factory methods on NumberFormat such as
* createInstance or createCurrencyInstance. If you need only minor adjustments
* to a standard format, you can modify the format returned by
* a NumberFormat factory method.
*
* @param pattern a non-localized pattern string
* @param symbolsToAdopt the set of symbols to be used. The caller should not
* delete this object after making this call.
* @param status Output param set to success/failure code. If the
* pattern is invalid this will be set to a failure code.
* @stable ICU 2.0
*/
DecimalFormat( const UnicodeString& pattern,
DecimalFormatSymbols* symbolsToAdopt,
UErrorCode& status);
/**
* Create a DecimalFormat from the given pattern and symbols.
* Use this constructor when you need to completely customize the
* behavior of the format.
* <P>
* To obtain standard formats for a given
* locale, use the factory methods on NumberFormat such as
* createInstance or createCurrencyInstance. If you need only minor adjustments
* to a standard format, you can modify the format returned by
* a NumberFormat factory method.
*
* @param pattern a non-localized pattern string
* @param symbolsToAdopt the set of symbols to be used. The caller should not
* delete this object after making this call.
* @param parseError Output param to receive errors occured during parsing
* @param status Output param set to success/failure code. If the
* pattern is invalid this will be set to a failure code.
* @stable ICU 2.0
*/
DecimalFormat( const UnicodeString& pattern,
DecimalFormatSymbols* symbolsToAdopt,
UParseError& parseError,
UErrorCode& status);
/**
* Create a DecimalFormat from the given pattern and symbols.
* Use this constructor when you need to completely customize the
* behavior of the format.
* <P>
* To obtain standard formats for a given
* locale, use the factory methods on NumberFormat such as
* createInstance or createCurrencyInstance. If you need only minor adjustments
* to a standard format, you can modify the format returned by
* a NumberFormat factory method.
*
* @param pattern a non-localized pattern string
* @param symbols the set of symbols to be used
* @param status Output param set to success/failure code. If the
* pattern is invalid this will be set to a failure code.
* @stable ICU 2.0
*/
DecimalFormat( const UnicodeString& pattern,
const DecimalFormatSymbols& symbols,
UErrorCode& status);
/**
* Copy constructor.
*
* @param source the DecimalFormat object to be copied from.
* @stable ICU 2.0
*/
DecimalFormat(const DecimalFormat& source);
/**
* Assignment operator.
*
* @param rhs the DecimalFormat object to be copied.
* @stable ICU 2.0
*/
DecimalFormat& operator=(const DecimalFormat& rhs);
/**
* Destructor.
* @stable ICU 2.0
*/
virtual ~DecimalFormat();
/**
* Clone this Format object polymorphically. The caller owns the
* result and should delete it when done.
*
* @return a polymorphic copy of this DecimalFormat.
* @stable ICU 2.0
*/
virtual Format* clone(void) const;
/**
* Return true if the given Format objects are semantically equal.
* Objects of different subclasses are considered unequal.
*
* @param other the object to be compared with.
* @return true if the given Format objects are semantically equal.
* @stable ICU 2.0
*/
virtual UBool operator==(const Format& other) const;
/**
* Format a double or long number using base-10 representation.
*
* @param number The value to be formatted.
* @param appendTo Output parameter to receive result.
* Result is appended to existing contents.
* @param pos On input: an alignment field, if desired.
* On output: the offsets of the alignment field.
* @return Reference to 'appendTo' parameter.
* @stable ICU 2.0
*/
virtual UnicodeString& format(double number,
UnicodeString& appendTo,
FieldPosition& pos) const;
/**
* Format a long number using base-10 representation.
*
* @param number The value to be formatted.
* @param appendTo Output parameter to receive result.
* Result is appended to existing contents.
* @param pos On input: an alignment field, if desired.
* On output: the offsets of the alignment field.
* @return Reference to 'appendTo' parameter.
* @stable ICU 2.0
*/
virtual UnicodeString& format(int32_t number,
UnicodeString& appendTo,
FieldPosition& pos) const;
/**
* Format an int64 number using base-10 representation.
*
* @param number The value to be formatted.
* @param appendTo Output parameter to receive result.
* Result is appended to existing contents.
* @param pos On input: an alignment field, if desired.
* On output: the offsets of the alignment field.
* @return Reference to 'appendTo' parameter.
* @stable ICU 2.8
*/
virtual UnicodeString& format(int64_t number,
UnicodeString& appendTo,
FieldPosition& pos) const;
/**
* Format a Formattable using base-10 representation.
*
* @param obj The value to be formatted.
* @param appendTo Output parameter to receive result.
* Result is appended to existing contents.
* @param pos On input: an alignment field, if desired.
* On output: the offsets of the alignment field.
* @param status Error code indicating success or failure.
* @return Reference to 'appendTo' parameter.
* @stable ICU 2.0
*/
virtual UnicodeString& format(const Formattable& obj,
UnicodeString& appendTo,
FieldPosition& pos,
UErrorCode& status) const;
/**
* Redeclared NumberFormat method.
* Formats an object to produce a string.
*
* @param obj The object to format.
* @param appendTo Output parameter to receive result.
* Result is appended to existing contents.
* @param status Output parameter filled in with success or failure status.
* @return Reference to 'appendTo' parameter.
* @stable ICU 2.0
*/
UnicodeString& format(const Formattable& obj,
UnicodeString& appendTo,
UErrorCode& status) const;
/**
* Redeclared NumberFormat method.
* Format a double number.
*
* @param number The value to be formatted.
* @param appendTo Output parameter to receive result.
* Result is appended to existing contents.
* @return Reference to 'appendTo' parameter.
* @stable ICU 2.0
*/
UnicodeString& format(double number,
UnicodeString& appendTo) const;
/**
* Redeclared NumberFormat method.
* Format a long number. These methods call the NumberFormat
* pure virtual format() methods with the default FieldPosition.
*
* @param number The value to be formatted.
* @param appendTo Output parameter to receive result.
* Result is appended to existing contents.
* @return Reference to 'appendTo' parameter.
* @stable ICU 2.0
*/
UnicodeString& format(int32_t number,
UnicodeString& appendTo) const;
/**
* Redeclared NumberFormat method.
* Format an int64 number. These methods call the NumberFormat
* pure virtual format() methods with the default FieldPosition.
*
* @param number The value to be formatted.
* @param appendTo Output parameter to receive result.
* Result is appended to existing contents.
* @return Reference to 'appendTo' parameter.
* @stable ICU 2.8
*/
UnicodeString& format(int64_t number,
UnicodeString& appendTo) const;
/**
* Parse the given string using this object's choices. The method
* does string comparisons to try to find an optimal match.
* If no object can be parsed, index is unchanged, and NULL is
* returned. The result is returned as the most parsimonious
* type of Formattable that will accomodate all of the
* necessary precision. For example, if the result is exactly 12,
* it will be returned as a long. However, if it is 1.5, it will
* be returned as a double.
*
* @param text The text to be parsed.
* @param result Formattable to be set to the parse result.
* If parse fails, return contents are undefined.
* @param 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.
* @see Formattable
* @stable ICU 2.0
*/
virtual void parse(const UnicodeString& text,
Formattable& result,
ParsePosition& parsePosition) const;
// Declare here again to get rid of function hiding problems.
/**
* Parse the given string using this object's choices.
*
* @param text The text to be parsed.
* @param result Formattable to be set to the parse result.
* @param status Output parameter filled in with success or failure status.
* @stable ICU 2.0
*/
virtual void parse(const UnicodeString& text,
Formattable& result,
UErrorCode& status) const;
/**
* 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.
*
* @param text the string to parse
* @param result output parameter to receive result. This will have
* its currency set to the parsed ISO currency code.
* @param 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.
* @return a reference to result
* @internal
*/
virtual Formattable& parseCurrency(const UnicodeString& text,
Formattable& result,
ParsePosition& pos) const;
/**
* Returns the decimal format symbols, which is generally not changed
* by the programmer or user.
* @return desired DecimalFormatSymbols
* @see DecimalFormatSymbols
* @stable ICU 2.0
*/
virtual const DecimalFormatSymbols* getDecimalFormatSymbols(void) const;
/**
* Sets the decimal format symbols, which is generally not changed
* by the programmer or user.
* @param symbolsToAdopt DecimalFormatSymbols to be adopted.
* @stable ICU 2.0
*/
virtual void adoptDecimalFormatSymbols(DecimalFormatSymbols* symbolsToAdopt);
/**
* Sets the decimal format symbols, which is generally not changed
* by the programmer or user.
* @param symbols DecimalFormatSymbols.
* @stable ICU 2.0
*/
virtual void setDecimalFormatSymbols(const DecimalFormatSymbols& symbols);
/**
* Get the positive prefix.
*
* @param result Output param which will receive the positive prefix.
* @return A reference to 'result'.
* Examples: +123, $123, sFr123
* @stable ICU 2.0
*/
UnicodeString& getPositivePrefix(UnicodeString& result) const;
/**
* Set the positive prefix.
*
* @param newValue the new value of the the positive prefix to be set.
* Examples: +123, $123, sFr123
* @stable ICU 2.0
*/
virtual void setPositivePrefix(const UnicodeString& newValue);
/**
* Get the negative prefix.
*
* @param result Output param which will receive the negative prefix.
* @return A reference to 'result'.
* Examples: -123, ($123) (with negative suffix), sFr-123
* @stable ICU 2.0
*/