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Location:
e32cmn.h
Link against: euser.lib
class TChar;
Holds a character value and provides a number of utility functions to manipulate it and test its properties.
For example, there are functions to convert the character to uppercase and test whether or not it is a control character.
The character value is stored as a 32-bit unsigned integer. The shorthand "TChar value" is used to describe the character value wrapped by a TChar object.
TChar can be used to represent Unicode values outside plane 0 (that is, the extended Unicode range from 0x10000 to 0xFFFFF). This differentiates it from TText which can only be used for 16-bit Unicode character values.
Defined in TChar
:
Compose()
, Decompose()
, EAlphaGroup
, EArabicNumber
, EBoundaryNeutral
, ECcCategory
, ECfCategory
, ECnCategory
, ECoCategory
, ECommonNumberSeparator
, EControlGroup
, ECsCategory
, EEuropeanNumber
, EEuropeanNumberSeparator
, EEuropeanNumberTerminator
, EFoldAccents
, EFoldAll
, EFoldCase
, EFoldDigits
, EFoldKana
, EFoldSpaces
, EFoldStandard
, EFoldWidth
, EFullWidth
, EHalfWidth
, ELeftToRight
, ELeftToRightEmbedding
, ELeftToRightOverride
, ELetterModifierGroup
, ELetterOtherGroup
, ELlCategory
, ELmCategory
, ELoCategory
, ELtCategory
, ELuCategory
, EMarkGroup
, EMaxAssignedCategory
, EMaxAssignedGroup
, EMaxGraphicCategory
, EMaxLetterCategory
, EMaxLetterOrLetterModifierCategory
, EMaxPrintableCategory
, EMcCategory
, EMeCategory
, EMnCategory
, ENarrow
, ENdCategory
, ENeutralWidth
, ENlCategory
, ENoCategory
, ENonSpacingMark
, ENumberGroup
, EOtherNeutral
, EParagraphSeparator
, EPcCategory
, EPdCategory
, EPeCategory
, EPfCategory
, EPiCategory
, EPoCategory
, EPopDirectionalFormat
, EPsCategory
, EPunctuationGroup
, ERightToLeft
, ERightToLeftArabic
, ERightToLeftEmbedding
, ERightToLeftOverride
, EScCategory
, ESegmentSeparator
, ESeparatorGroup
, EShiftJIS
, ESkCategory
, ESmCategory
, ESoCategory
, ESymbolGroup
, EUnassignedGroup
, EUnicode
, EWhitespace
, EWide
, EZlCategory
, EZpCategory
, EZsCategory
, Eos()
, Fold()
, Fold()
, GetBdCategory()
, GetCategory()
, GetCjkWidth()
, GetCombiningClass()
, GetInfo()
, GetLowerCase()
, GetNumericValue()
, GetTitleCase()
, GetUpperCase()
, IsAlpha()
, IsAlphaDigit()
, IsAssigned()
, IsControl()
, IsDigit()
, IsGraph()
, IsHexDigit()
, IsLower()
, IsMirrored()
, IsPrint()
, IsPunctuation()
, IsSpace()
, IsTitle()
, IsUpper()
, LowerCase()
, SetChar()
, TBdCategory
, TCategory
, TChar()
, TChar()
, TCharInfo
, TCjkWidth
, TEncoding
, TitleCase()
, UpperCase()
, anonymous
, operator TUint()
, operator+()
, operator+=()
, operator-()
, operator-=()
inline TChar();
Default constructor.
Constructs this character object with an undefined value.
inline TChar(TUint aChar);
Constructs this character object and initialises it with the specified value.
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inline TChar &operator-=(TUint aChar);
Subtracts an unsigned integer value from this character object.
This character object is changed by the operation.
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inline TChar &operator+=(TUint aChar);
Adds an unsigned integer value to this character object.
This character object is changed by the operation.
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inline TChar operator-(TUint aChar);
Gets the result of subtracting an unsigned integer value from this character object.
This character object is not changed.
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inline TChar operator+(TUint aChar);
Gets the result of adding an unsigned integer value to this character object.
This character object is not changed.
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inline operator TUint() const;
Gets the value of the character as an unsigned integer.
The operator casts a TChar to a TUint, returning the TUint value wrapped by this character object.
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inline void Fold();
Converts the character to a form which can be used in tolerant comparisons without control over the operations performed.
Tolerant comparisons are those which ignore character differences like case and accents.
This function can be used when searching for a string in a text file or a file in a directory. Folding performs the following conversions: converts to lowercase, strips accents, converts all digits representing the values 0..9 to the ordinary digit characters '0'..'9', converts all spaces (standard, non-break, fixed-width, ideographic, etc.) to the ordinary space character (0x0020), converts Japanese characters in the hiragana syllabary to katakana, and converts East Asian halfwidth and fullwidth variants to their ordinary forms. You can choose to perform any subset of these operations by using the other function overload.
inline void LowerCase();
Converts the character to its lowercase form.
Characters lacking a lowercase form are unchanged.
inline void UpperCase();
Converts the character to its uppercase form.
Characters lacking an uppercase form are unchanged.
inline TBool Eos() const;
Tests whether the character is the C/C++ end-of-string character - 0.
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IMPORT_C TUint GetUpperCase() const;
Gets the character value after conversion to uppercase or the character's own value, if no uppercase form exists.
The character object itself is not changed.
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IMPORT_C TUint GetLowerCase() const;
Gets the character value after conversion to lowercase or the character's own value, if no lowercase form exists.
The character object itself is not changed.
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IMPORT_C TBool IsLower() const;
Tests whether the character is lowercase.
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IMPORT_C TBool IsUpper() const;
Tests whether the character is uppercase.
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IMPORT_C TBool IsAlpha() const;
Tests whether the character is alphabetic.
For Unicode, the function returns TRUE for all letters, including those from syllabaries and ideographic scripts. The function returns FALSE for letter-like characters that are in fact diacritics. Specifically, the function returns TRUE for categories: ELuCategory, ELtCategory, ELlCategory, and ELoCategory; it returns FALSE for all other categories including ELmCategory.
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IMPORT_C TBool IsDigit() const;
Tests whether the character is a standard decimal digit.
For Unicode, this function returns TRUE only for the digits '0'...'9' (U+0030...U+0039), not for other digits in scripts like Arabic, Tamil, etc.
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IMPORT_C TBool IsAlphaDigit() const;
Tests whether the character is alphabetic or a decimal digit.
It is identical to (IsAlpha()
||IsDigit()).
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IMPORT_C TBool IsHexDigit() const;
Tests whether the character is a hexadecimal digit (0-9, a-f, A-F).
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IMPORT_C TBool IsSpace() const;
Tests whether the character is a white space character.
White space includes spaces, tabs and separators.
For Unicode, the function returns TRUE for all characters in the categories: EZsCategory, EZlCategory and EZpCategory, and also for the characters 0x0009 (horizontal tab), 0x000A (linefeed), 0x000B (vertical tab), 0x000C (form feed), and 0x000D (carriage return).
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IMPORT_C TBool IsPunctuation() const;
Tests whether the character is a punctuation character.
For Unicode, punctuation characters are any character in the categories: EPcCategory, EPdCategory, EPsCategory, EPeCategory, EPiCategory, EPfCategory, EPoCategory.
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IMPORT_C TBool IsGraph() const;
Tests whether the character is a graphic character.
For Unicode, graphic characters include printable characters but not the space character. Specifically, graphic characters are any character except those in categories: EZsCategory,EZlCategory,EZpCategory, ECcCategory,ECfCategory, ECsCategory, ECoCategory, and ,ECnCategory.
Note that for ISO Latin-1, all alphanumeric and punctuation characters are graphic.
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IMPORT_C TBool IsPrint() const;
Tests whether the character is a printable character.
For Unicode, printable characters are any character except those in categories: ECcCategory, ECfCategory, ECsCategory, ECoCategory and ECnCategory.
Note that for ISO Latin-1, all alphanumeric and punctuation characters, plus space, are printable.
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IMPORT_C TBool IsControl() const;
Tests whether the character is a control character.
For Unicode, the function returns TRUE for all characters in the categories: ECcCategory, ECfCategory, ECsCategory, ECoCategory and ECnCategoryCc.
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inline void Fold(TInt aFlags);
Converts the character to a form which can be used in tolerant comparisons allowing selection of the specific fold operations to be performed.
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inline void TitleCase();
Converts the character to its titlecase form.
The titlecase form of a character is identical to its uppercase form unless a specific titlecase form exists. Characters lacking a titlecase form are unchanged.
IMPORT_C TUint GetTitleCase() const;
Gets the character value after conversion to titlecase or the character's own value, if no titlecase form exists.
The titlecase form of a character is identical to its uppercase form unless a specific titlecase form exists.
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IMPORT_C TBool IsTitle() const;
Tests whether this character is in titlecase.
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IMPORT_C TBool IsAssigned() const;
Tests whether this character has an assigned meaning in the Unicode encoding.
All characters outside the range 0x0000 - 0xFFFF are unassigned and there are also many unassigned characters within the Unicode range.
Locales can change the assigned/unassigned status of characters. This means that the precise behaviour of this function is locale-dependent.
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IMPORT_C void GetInfo(TCharInfo &aInfo) const;
Gets this character;s standard category information.
This includes everything except its CJK width and decomposition, if any.
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IMPORT_C TCategory GetCategory() const;
Gets this character's Unicode category.
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IMPORT_C TBdCategory GetBdCategory() const;
Gets the bi-directional category of a character.
For more information on the bi-directional algorithm, see Unicode Technical Report No. 9 available at: http://www.unicode.org/unicode/reports/tr9/.
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IMPORT_C TInt GetCombiningClass() const;
Gets this character's combining class.
Note that diacritics and other combining characters have non-zero combining classes.
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IMPORT_C TBool IsMirrored() const;
Tests whether this character has the mirrored property.
Mirrored characters, like ( ) [ ] < >, change direction according to the directionality of the surrounding characters. For example, an opening parenthesis 'faces right' in Hebrew or Arabic, and to say that 2 < 3 you would have to say that 3 > 2, where the '>' is, in this example, a less-than sign to be read right-to-left.
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IMPORT_C TInt GetNumericValue() const;
Gets the integer numeric value of this character.
Numeric values need not be in the range 0..9; the Unicode character set includes various other numeric characters such as the Roman and Tamil numerals for 500, 1000, etc.
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IMPORT_C TCjkWidth GetCjkWidth() const;
Gets the Chinese, Japanese, Korean (CJK) notional width.
Some display systems used in East Asia display characters on a grid of fixed-width character cells like the standard MSDOS display mode.
Some characters, e.g. the Japanese katakana syllabary, take up a single character cell and some characters, e.g., kanji, Chinese characters used in Japanese, take up two. These are called half-width and full-width characters. This property is fixed and cannot be overridden for particular locales.
For more information on returned widths, see Unicode Technical Report 11 on East Asian Width available at: http://www.unicode.org/unicode/reports/tr11/
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static IMPORT_C TBool Compose(TUint &aResult, const TDesC16 &aSource);
Composes a string of Unicode characters to produce a single character result.
For example, 0061 ('a') and 030A (combining ring above) compose to give 00E5 ('a' with ring above).
A canonical decomposition is a relationship between a string of characters - usually a base character and one or more diacritics - and a composed character. The Unicode standard requires that compliant software treats composed characters identically with their canonical decompositions. The mappings used by these functions are fixed and cannot be overridden for particular locales.
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IMPORT_C TBool Decompose(TPtrC16 &aResult) const;
Maps this character to its maximal canonical decomposition.
For example, 01E1 ('a' with dot above and macron) decomposes into 0061 ('a') 0307 (dot) and 0304 (macron).
Note that this function is used during collation, as performed by the Mem::CompareC()
function, to convert the compared strings to their maximal canonical decompositions.
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struct TCharInfo;
A structure to hold information about a Unicode character.
An object of this type is passed to TChar::GetInfo()
.
Defined in TChar::TCharInfo
:
iBdCategory
, iCategory
, iCombiningClass
, iLowerCase
, iMirrored
, iNumericValue
, iTitleCase
, iUpperCase
iCategory
TCategory iCategory;
General category.
iBdCategory
TBdCategory iBdCategory;
Bi-directional category.
iCombiningClass
TInt iCombiningClass;
Combining class: number (currently) in the range 0..234
iLowerCase
TUint iLowerCase;
Lower case form.
iUpperCase
TUint iUpperCase;
Upper case form.
iTitleCase
TUint iTitleCase;
Title case form.
iMirrored
TBool iMirrored;
True, if the character is mirrored.
iNumericValue
TInt iNumericValue;
Integer numeric value: -1 if none, -2 if a fraction.
TCategory
General Unicode character category.
The high nibble encodes the major category (Mark, Number, etc.) and a low nibble encodes the subdivisions of that category.
The category codes can be used in three ways:
(i) as unique constants: there is one for each Unicode category, with a name of the form
E<XX>Category
where
<XX>
is the category name given by the Unicode database (e.g., the constant ELuCategory is used for lowercase letters, category Lu);
(ii) as numbers in certain ranges: letter categories are all <= EMaxLetterCategory;
(iii) as codes in which the upper nibble gives the category group (e.g., punctuation categories all yield TRUE for the test (category & 0xF0) ==EPunctuationGroup).
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TBdCategory
The bi-directional Unicode character category.
For more information on the bi-directional algorithm, see Unicode Technical Report No. 9 available at: http://www.unicode.org/unicode/reports/tr9.
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TCjkWidth
Notional character width as known to East Asian (Chinese, Japanese, Korean (CJK)) coding systems.
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TEncoding
Encoding systems used by the translation functions.
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n/a
Flags defining operations to be performed using TChar::Fold()
.
The flag values are passed to the Fold()
funtion.
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