ICU 76.1 76.1
icu::FieldPosition Class Reference

FieldPosition is a simple class used by Format and its subclasses to identify fields in formatted output. More...

#include <fieldpos.h>

Inheritance diagram for icu::FieldPosition:
icu::UObject icu::UMemory

Public Types

enum  { DONT_CARE = -1 }
 DONT_CARE may be specified as the field to indicate that the caller doesn't need to specify a field. More...
 

Public Member Functions

 FieldPosition ()
 Creates a FieldPosition object with a non-specified field.
 
 FieldPosition (int32_t field)
 Creates a FieldPosition object for the given field.
 
 FieldPosition (const FieldPosition &copy)
 Copy constructor.
 
virtual ~FieldPosition ()
 Destructor.
 
FieldPositionoperator= (const FieldPosition &copy)
 Assignment operator.
 
bool operator== (const FieldPosition &that) const
 Equality operator.
 
bool operator!= (const FieldPosition &that) const
 Equality operator.
 
FieldPositionclone () const
 Clone this object.
 
int32_t getField () const
 Retrieve the field identifier.
 
int32_t getBeginIndex () const
 Retrieve the index of the first character in the requested field.
 
int32_t getEndIndex () const
 Retrieve the index of the character following the last character in the requested field.
 
void setField (int32_t f)
 Set the field.
 
void setBeginIndex (int32_t bi)
 Set the begin index.
 
void setEndIndex (int32_t ei)
 Set the end index.
 
virtual UClassID getDynamicClassID () const override
 ICU "poor man's RTTI", returns a UClassID for the actual class.
 
- Public Member Functions inherited from icu::UObject
virtual ~UObject ()
 Destructor.
 

Static Public Member Functions

static UClassID getStaticClassID ()
 ICU "poor man's RTTI", returns a UClassID for this class.
 

Detailed Description

FieldPosition is a simple class used by Format and its subclasses to identify fields in formatted output.

Fields are identified by constants, whose names typically end with _FIELD, defined in the various subclasses of Format. See ERA_FIELD and its friends in DateFormat for an example.

FieldPosition keeps track of the position of the field within the formatted output with two indices: the index of the first character of the field and the index of the last character of the field.

One version of the format method in the various Format classes requires a FieldPosition object as an argument. You use this format method to perform partial formatting or to get information about the formatted output (such as the position of a field).

The FieldPosition class is not intended for public subclassing.

Below is an example of using FieldPosition to aid alignment of an array of formatted floating-point numbers on their decimal points:

double doubleNum[] = {123456789.0, -12345678.9, 1234567.89, -123456.789,
12345.6789, -1234.56789, 123.456789, -12.3456789, 1.23456789};
int dNumSize = (int)(sizeof(doubleNum)/sizeof(double));
const int tempLen = 20;
char temp[tempLen];
for (int i=0; i<dNumSize; i++) {
char fmtText[tempLen];
ToCharString(fmt->format(doubleNum[i], buf, pos), fmtText);
for (int j=0; j<tempLen; j++) temp[j] = ' '; // clear with spaces
temp[__min(tempLen, tempLen-pos.getEndIndex())] = '\0';
cout << temp << fmtText << endl;
}
delete fmt;
IMPORTANT: New users are strongly encouraged to see if numberformatter.h fits their use case.
Definition decimfmt.h:666
virtual void setDecimalSeparatorAlwaysShown(UBool newValue)
Allows you to set the behavior of the decimal separator with integers.
UnicodeString & format(double number, UnicodeString &appendTo, FieldPosition &pos) const override
Format a double or long number using base-10 representation.
FieldPosition is a simple class used by Format and its subclasses to identify fields in formatted out...
Definition fieldpos.h:110
@ INTEGER_FIELD
These constants are provided for backwards compatibility only.
Definition numfmt.h:267
static NumberFormat * createInstance(UErrorCode &)
Create a default style NumberFormat for the current default locale.
UnicodeString is a string class that stores Unicode characters directly and provides similar function...
Definition unistr.h:296
UErrorCode
Standard ICU4C error code type, a substitute for exceptions.
Definition utypes.h:430
@ U_ZERO_ERROR
No error, no warning.
Definition utypes.h:465

<p<blockquote>‍ The code will generate the following output:

123,456,789.000
-12,345,678.900
1,234,567.880
-123,456.789
12,345.678
-1,234.567
123.456
-12.345
1.234

Definition at line 110 of file fieldpos.h.

Member Enumeration Documentation

◆ anonymous enum

anonymous enum

DONT_CARE may be specified as the field to indicate that the caller doesn't need to specify a field.

Stable
ICU 2.0

Definition at line 117 of file fieldpos.h.

Constructor & Destructor Documentation

◆ FieldPosition() [1/3]

icu::FieldPosition::FieldPosition ( )
inline

Creates a FieldPosition object with a non-specified field.

Stable
ICU 2.0

Definition at line 123 of file fieldpos.h.

◆ FieldPosition() [2/3]

icu::FieldPosition::FieldPosition ( int32_t field)
inline

Creates a FieldPosition object for the given field.

Fields are identified by constants, whose names typically end with _FIELD, in the various subclasses of Format.

See also
NumberFormat::INTEGER_FIELD
NumberFormat::FRACTION_FIELD
DateFormat::YEAR_FIELD
DateFormat::MONTH_FIELD
Stable
ICU 2.0

Definition at line 137 of file fieldpos.h.

◆ FieldPosition() [3/3]

icu::FieldPosition::FieldPosition ( const FieldPosition & copy)
inline

Copy constructor.

Parameters
copythe object to be copied from.
Stable
ICU 2.0

Definition at line 145 of file fieldpos.h.

◆ ~FieldPosition()

virtual icu::FieldPosition::~FieldPosition ( )
virtual

Destructor.

Stable
ICU 2.0

Member Function Documentation

◆ clone()

FieldPosition * icu::FieldPosition::clone ( ) const

Clone this object.

Clones can be used concurrently in multiple threads. If an error occurs, then nullptr is returned. The caller must delete the clone.

Returns
a clone of this object
See also
getDynamicClassID
Stable
ICU 2.8

◆ getBeginIndex()

int32_t icu::FieldPosition::getBeginIndex ( ) const
inline

Retrieve the index of the first character in the requested field.

Returns
the index of the first character in the requested field.
Stable
ICU 2.0

Definition at line 202 of file fieldpos.h.

◆ getDynamicClassID()

virtual UClassID icu::FieldPosition::getDynamicClassID ( ) const
overridevirtual

ICU "poor man's RTTI", returns a UClassID for the actual class.

Stable
ICU 2.2

Reimplemented from icu::UObject.

◆ getEndIndex()

int32_t icu::FieldPosition::getEndIndex ( ) const
inline

Retrieve the index of the character following the last character in the requested field.

Returns
the index of the character following the last character in the requested field.
Stable
ICU 2.0

Definition at line 211 of file fieldpos.h.

◆ getField()

int32_t icu::FieldPosition::getField ( ) const
inline

Retrieve the field identifier.

Returns
the field identifier.
Stable
ICU 2.0

Definition at line 195 of file fieldpos.h.

◆ getStaticClassID()

static UClassID icu::FieldPosition::getStaticClassID ( )
static

ICU "poor man's RTTI", returns a UClassID for this class.

Stable
ICU 2.2

◆ operator!=()

bool icu::FieldPosition::operator!= ( const FieldPosition & that) const
inline

Equality operator.

Parameters
thatthe object to be compared with.
Returns
true if the two field positions are not equal, false otherwise.
Stable
ICU 2.0

Definition at line 286 of file fieldpos.h.

References icu::operator==().

◆ operator=()

FieldPosition & icu::FieldPosition::operator= ( const FieldPosition & copy)
inline

Assignment operator.

Parameters
copythe object to be copied from.
Stable
ICU 2.0

Definition at line 269 of file fieldpos.h.

◆ operator==()

bool icu::FieldPosition::operator== ( const FieldPosition & that) const
inline

Equality operator.

Parameters
thatthe object to be compared with.
Returns
true if the two field positions are equal, false otherwise.
Stable
ICU 2.0

Definition at line 278 of file fieldpos.h.

◆ setBeginIndex()

void icu::FieldPosition::setBeginIndex ( int32_t bi)
inline

Set the begin index.

For use by subclasses of Format.

Parameters
bithe new value of the begin index
Stable
ICU 2.0

Definition at line 225 of file fieldpos.h.

◆ setEndIndex()

void icu::FieldPosition::setEndIndex ( int32_t ei)
inline

Set the end index.

For use by subclasses of Format.

Parameters
eithe new value of the end index
Stable
ICU 2.0

Definition at line 232 of file fieldpos.h.

◆ setField()

void icu::FieldPosition::setField ( int32_t f)
inline

Set the field.

Parameters
fthe new value of the field.
Stable
ICU 2.0

Definition at line 218 of file fieldpos.h.


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