#include "unicode/ucol.h"
Go to the source code of this file.
Defines | |
#define | UCOL_NULLORDER 0xFFFFFFFF |
This indicates an error has occured during processing or if no more CEs is to be returned. | |
Typedefs | |
typedef UCollationElements | UCollationElements |
The UCollationElements struct. | |
Functions | |
U_CAPI UCollationElements *U_EXPORT2 | ucol_openElements (const UCollator *coll, const UChar *text, int32_t textLength, UErrorCode *status) |
Open the collation elements for a string. | |
U_CAPI int32_t U_EXPORT2 | ucol_keyHashCode (const uint8_t *key, int32_t length) |
get a hash code for a key... | |
U_CAPI void U_EXPORT2 | ucol_closeElements (UCollationElements *elems) |
Close a UCollationElements. | |
U_CAPI void U_EXPORT2 | ucol_reset (UCollationElements *elems) |
Reset the collation elements to their initial state. | |
U_CAPI int32_t U_EXPORT2 | ucol_next (UCollationElements *elems, UErrorCode *status) |
Get the ordering priority of the next collation element in the text. | |
U_CAPI int32_t U_EXPORT2 | ucol_previous (UCollationElements *elems, UErrorCode *status) |
Get the ordering priority of the previous collation element in the text. | |
U_CAPI int32_t U_EXPORT2 | ucol_getMaxExpansion (const UCollationElements *elems, int32_t order) |
Get the maximum length of any expansion sequences that end with the specified comparison order. | |
U_CAPI void U_EXPORT2 | ucol_setText (UCollationElements *elems, const UChar *text, int32_t textLength, UErrorCode *status) |
Set the text containing the collation elements. | |
U_CAPI int32_t U_EXPORT2 | ucol_getOffset (const UCollationElements *elems) |
Get the offset of the current source character. | |
U_CAPI void U_EXPORT2 | ucol_setOffset (UCollationElements *elems, int32_t offset, UErrorCode *status) |
Set the offset of the current source character. |
The UCollationElements API is used as an iterator to walk through each character of an international string. Use the iterator to return the ordering priority of the positioned character. The ordering priority of a character, which we refer to as a key, defines how a character is collated in the given collation object. For example, consider the following in Spanish:
. "ca" -> the first key is key('c') and second key is key('a'). . "cha" -> the first key is key('ch') and second key is key('a').And in German,. "<ae ligature>b"-> the first key is key('a'), the second key is key('e'), and . the third key is key('b').Example of the iterator usage: (without error checking)
. void CollationElementIterator_Example() . { . UChar *s; . t_int32 order, primaryOrder; . UCollationElements *c; . UCollatorOld *coll; . UErrorCode success = U_ZERO_ERROR; . s=(UChar*)malloc(sizeof(UChar) * (strlen("This is a test")+1) ); . u_uastrcpy(s, "This is a test"); . coll = ucol_open(NULL, &success); . c = ucol_openElements(coll, str, u_strlen(str), &status); . order = ucol_next(c, &success); . ucol_reset(c); . order = ucol_prev(c, &success); . free(s); . ucol_close(coll); . ucol_closeElements(c); . }ucol_next() returns the collation order of the next. ucol_prev() returns the collation order of the previous character. The Collation Element Iterator moves only in one direction between calls to ucol_reset. That is, ucol_next() and ucol_prev can not be inter-used. Whenever ucol_prev is to be called after ucol_next() or vice versa, ucol_reset has to be called first to reset the status, shifting pointers to either the end or the start of the string. Hence at the next call of ucol_prev or ucol_next, the first or last collation order will be returned. If a change of direction is done without a ucol_reset, the result is undefined. The result of a forward iterate (ucol_next) and reversed result of the backward iterate (ucol_prev) on the same string are equivalent, if collation orders with the value UCOL_IGNORABLE are ignored. Character based on the comparison level of the collator. A collation order consists of primary order, secondary order and tertiary order. The data type of the collation order is t_int32.
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The UCollationElements struct. For usage in C programs. |
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Close a UCollationElements. Once closed, a UCollationElements may no longer be used.
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Get the maximum length of any expansion sequences that end with the specified comparison order. This is useful for .... ?
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Get the offset of the current source character. This is an offset into the text of the character containing the current collation elements.
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get a hash code for a key... Not very useful! |
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Get the ordering priority of the next collation element in the text. A single character may contain more than one collation element.
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Open the collation elements for a string.
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Get the ordering priority of the previous collation element in the text. A single character may contain more than one collation element. Note that internally a stack is used to store buffered collation elements. It is very rare that the stack will overflow, however if such a case is encountered, the problem can be solved by increasing the size UCOL_EXPAND_CE_BUFFER_SIZE in ucol_imp.h.
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Reset the collation elements to their initial state. This will move the 'cursor' to the beginning of the text. Property settings for collation will be reset to the current status.
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Set the offset of the current source character. This is an offset into the text of the character to be processed. Property settings for collation will remain the same. In order to reset the iterator to the current collation property settings, the API reset() has to be called.
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Set the text containing the collation elements. Property settings for collation will remain the same. In order to reset the iterator to the current collation property settings, the API reset() has to be called.
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