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1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4  *******************************************************************************
5  * Copyright (C) 1996-2016, International Business Machines
6  * Corporation and others. All Rights Reserved.
7  *******************************************************************************
8 */
9 
10 #ifndef UDAT_H
11 #define UDAT_H
12 
13 #include "unicode/utypes.h"
14 
15 #if !UCONFIG_NO_FORMATTING
16 
17 #include "unicode/localpointer.h"
18 #include "unicode/ucal.h"
19 #include "unicode/unum.h"
20 #include "unicode/udisplaycontext.h"
21 #include "unicode/ufieldpositer.h"
22 /**
23  * \file
24  * \brief C API: DateFormat
25  *
26  * <h2> Date Format C API</h2>
27  *
28  * Date Format C API  consists of functions that convert dates and
29  * times from their internal representations to textual form and back again in a
30  * language-independent manner. Converting from the internal representation (milliseconds
31  * since midnight, January 1, 1970) to text is known as "formatting," and converting
32  * from text to millis is known as "parsing."  We currently define only one concrete
33  * structure UDateFormat, which can handle pretty much all normal
34  * date formatting and parsing actions.
35  * <P>
36  * Date Format helps you to format and parse dates for any locale. Your code can
37  * be completely independent of the locale conventions for months, days of the
38  * week, or even the calendar format: lunar vs. solar.
39  * <P>
40  * To format a date for the current Locale with default time and date style,
41  * use one of the static factory methods:
42  * <pre>
43  * \code
44  *  UErrorCode status = U_ZERO_ERROR;
45  *  UChar *myString;
46  *  int32_t myStrlen = 0;
47  *  UDateFormat* dfmt = udat_open(UDAT_DEFAULT, UDAT_DEFAULT, NULL, NULL, -1, NULL, -1, &status);
48  *  myStrlen = udat_format(dfmt, myDate, NULL, myStrlen, NULL, &status);
49  *  if (status==U_BUFFER_OVERFLOW_ERROR){
50  *      status=U_ZERO_ERROR;
51  *      myString=(UChar*)malloc(sizeof(UChar) * (myStrlen+1) );
52  *      udat_format(dfmt, myDate, myString, myStrlen+1, NULL, &status);
53  *  }
54  * \endcode
55  * </pre>
56  * If you are formatting multiple numbers, it is more efficient to get the
57  * format and use it multiple times so that the system doesn't have to fetch the
58  * information about the local language and country conventions multiple times.
59  * <pre>
60  * \code
61  *  UErrorCode status = U_ZERO_ERROR;
62  *  int32_t i, myStrlen = 0;
63  *  UChar* myString;
64  *  char buffer[1024];
65  *  UDate myDateArr[] = { 0.0, 100000000.0, 2000000000.0 }; // test values
66  *  UDateFormat* df = udat_open(UDAT_DEFAULT, UDAT_DEFAULT, NULL, NULL, -1, NULL, 0, &status);
67  *  for (i = 0; i < 3; i++) {
68  *      myStrlen = udat_format(df, myDateArr[i], NULL, myStrlen, NULL, &status);
69  *      if(status == U_BUFFER_OVERFLOW_ERROR){
70  *          status = U_ZERO_ERROR;
71  *          myString = (UChar*)malloc(sizeof(UChar) * (myStrlen+1) );
72  *          udat_format(df, myDateArr[i], myString, myStrlen+1, NULL, &status);
73  *          printf("%s\n", u_austrcpy(buffer, myString) );
74  *          free(myString);
75  *      }
76  *  }
77  * \endcode
78  * </pre>
79  * To get specific fields of a date, you can use UFieldPosition to
80  * get specific fields.
81  * <pre>
82  * \code
83  *  UErrorCode status = U_ZERO_ERROR;
84  *  UFieldPosition pos;
85  *  UChar *myString;
86  *  int32_t myStrlen = 0;
87  *  char buffer[1024];
88  *
89  *  pos.field = 1;  // Same as the DateFormat::EField enum
90  *  UDateFormat* dfmt = udat_open(UDAT_DEFAULT, UDAT_DEFAULT, NULL, -1, NULL, 0, &status);
91  *  myStrlen = udat_format(dfmt, myDate, NULL, myStrlen, &pos, &status);
92  *  if (status==U_BUFFER_OVERFLOW_ERROR){
93  *      status=U_ZERO_ERROR;
94  *      myString=(UChar*)malloc(sizeof(UChar) * (myStrlen+1) );
95  *      udat_format(dfmt, myDate, myString, myStrlen+1, &pos, &status);
96  *  }
97  *  printf("date format: %s\n", u_austrcpy(buffer, myString));
98  *  buffer[pos.endIndex] = 0;   // NULL terminate the string.
99  *  printf("UFieldPosition position equals %s\n", &buffer[pos.beginIndex]);
100  * \endcode
101  * </pre>
102  * To format a date for a different Locale, specify it in the call to
103  * udat_open()
104  * <pre>
105  * \code
106  *        UDateFormat* df = udat_open(UDAT_SHORT, UDAT_SHORT, "fr_FR", NULL, -1, NULL, 0, &status);
107  * \endcode
108  * </pre>
109  * You can use a DateFormat API udat_parse() to parse.
110  * <pre>
111  * \code
112  *  UErrorCode status = U_ZERO_ERROR;
113  *  int32_t parsepos=0;
114  *  UDate myDate = udat_parse(df, myString, u_strlen(myString), &parsepos, &status);
115  * \endcode
116  * </pre>
117  *  You can pass in different options for the arguments for date and time style
118  *  to control the length of the result; from SHORT to MEDIUM to LONG to FULL.
119  *  The exact result depends on the locale, but generally:
120  *  see UDateFormatStyle for more details
121  * <ul type=round>
122  *   <li>   UDAT_SHORT is completely numeric, such as 12/13/52 or 3:30pm
123  *   <li>   UDAT_MEDIUM is longer, such as Jan 12, 1952
124  *   <li>   UDAT_LONG is longer, such as January 12, 1952 or 3:30:32pm
125  *   <li>   UDAT_FULL is pretty completely specified, such as
126  *          Tuesday, April 12, 1952 AD or 3:30:42pm PST.
127  * </ul>
128  * You can also set the time zone on the format if you wish.
129  * <P>
130  * You can also use forms of the parse and format methods with Parse Position and
131  * UFieldPosition to allow you to
132  * <ul type=round>
133  *   <li>   Progressively parse through pieces of a string.
134  *   <li>   Align any particular field, or find out where it is for selection
135  *          on the screen.
136  * </ul>
137  * <p><strong>Date and Time Patterns:</strong></p>
138  *
139  * <p>Date and time formats are specified by <em>date and time pattern</em> strings.
140  * Within date and time pattern strings, all unquoted ASCII letters [A-Za-z] are reserved
141  * as pattern letters representing calendar fields. <code>UDateFormat</code> supports
142  * the date and time formatting algorithm and pattern letters defined by
143  * <a href="http://www.unicode.org/reports/tr35/tr35-dates.html#Date_Field_Symbol_Table">UTS#35
144  * Unicode Locale Data Markup Language (LDML)</a> and further documented for ICU in the
145  * <a href="https://sites.google.com/site/icuprojectuserguide/formatparse/datetime?pli=1#TOC-Date-Field-Symbol-Table">ICU
146  * User Guide</a>.</p>
147  */
148 
149 /** A date formatter.
150  *  For usage in C programs.
151  *  @stable ICU 2.6
152  */
153 typedef void* UDateFormat;
154 
155 /** The possible date/time format styles
156  *  @stable ICU 2.6
157  */
158 typedef enum UDateFormatStyle {
159     /** Full style */
160     UDAT_FULL,
161     /** Long style */
162     UDAT_LONG,
163     /** Medium style */
164     UDAT_MEDIUM,
165     /** Short style */
166     UDAT_SHORT,
167     /** Default style */
168     UDAT_DEFAULT = UDAT_MEDIUM,
169 
170     /** Bitfield for relative date */
171     UDAT_RELATIVE = (1 << 7),
172 
173     UDAT_FULL_RELATIVE = UDAT_FULL | UDAT_RELATIVE,
174 
175     UDAT_LONG_RELATIVE = UDAT_LONG | UDAT_RELATIVE,
176 
177     UDAT_MEDIUM_RELATIVE = UDAT_MEDIUM | UDAT_RELATIVE,
178 
179     UDAT_SHORT_RELATIVE = UDAT_SHORT | UDAT_RELATIVE,
180 
181 
182     /** No style */
183     UDAT_NONE = -1,
184 
185     /**
186      * Use the pattern given in the parameter to udat_open
187      * @see udat_open
188      * @stable ICU 50
189      */
190     UDAT_PATTERN = -2,
191 
192 #ifndef U_HIDE_INTERNAL_API
193     /** @internal alias to UDAT_PATTERN */
194     UDAT_IGNORE = UDAT_PATTERN
195 #endif /* U_HIDE_INTERNAL_API */
196 } UDateFormatStyle;
197 
198 /* Skeletons for dates. */
199 
200 /**
201  * Constant for date skeleton with year.
202  * @stable ICU 4.0
203  */
204 #define UDAT_YEAR                       "y"
205 /**
206  * Constant for date skeleton with quarter.
207  * @stable ICU 51
208  */
209 #define UDAT_QUARTER                    "QQQQ"
210 /**
211  * Constant for date skeleton with abbreviated quarter.
212  * @stable ICU 51
213  */
214 #define UDAT_ABBR_QUARTER               "QQQ"
215 /**
216  * Constant for date skeleton with year and quarter.
217  * @stable ICU 4.0
218  */
219 #define UDAT_YEAR_QUARTER               "yQQQQ"
220 /**
221  * Constant for date skeleton with year and abbreviated quarter.
222  * @stable ICU 4.0
223  */
224 #define UDAT_YEAR_ABBR_QUARTER          "yQQQ"
225 /**
226  * Constant for date skeleton with month.
227  * @stable ICU 4.0
228  */
229 #define UDAT_MONTH                      "MMMM"
230 /**
231  * Constant for date skeleton with abbreviated month.
232  * @stable ICU 4.0
233  */
234 #define UDAT_ABBR_MONTH                 "MMM"
235 /**
236  * Constant for date skeleton with numeric month.
237  * @stable ICU 4.0
238  */
239 #define UDAT_NUM_MONTH                  "M"
240 /**
241  * Constant for date skeleton with year and month.
242  * @stable ICU 4.0
243  */
244 #define UDAT_YEAR_MONTH                 "yMMMM"
245 /**
246  * Constant for date skeleton with year and abbreviated month.
247  * @stable ICU 4.0
248  */
249 #define UDAT_YEAR_ABBR_MONTH            "yMMM"
250 /**
251  * Constant for date skeleton with year and numeric month.
252  * @stable ICU 4.0
253  */
254 #define UDAT_YEAR_NUM_MONTH             "yM"
255 /**
256  * Constant for date skeleton with day.
257  * @stable ICU 4.0
258  */
259 #define UDAT_DAY                        "d"
260 /**
261  * Constant for date skeleton with year, month, and day.
262  * Used in combinations date + time, date + time + zone, or time + zone.
263  * @stable ICU 4.0
264  */
265 #define UDAT_YEAR_MONTH_DAY             "yMMMMd"
266 /**
267  * Constant for date skeleton with year, abbreviated month, and day.
268  * Used in combinations date + time, date + time + zone, or time + zone.
269  * @stable ICU 4.0
270  */
271 #define UDAT_YEAR_ABBR_MONTH_DAY        "yMMMd"
272 /**
273  * Constant for date skeleton with year, numeric month, and day.
274  * Used in combinations date + time, date + time + zone, or time + zone.
275  * @stable ICU 4.0
276  */
277 #define UDAT_YEAR_NUM_MONTH_DAY         "yMd"
278 /**
279  * Constant for date skeleton with weekday.
280  * @stable ICU 51
281  */
282 #define UDAT_WEEKDAY                    "EEEE"
283 /**
284  * Constant for date skeleton with abbreviated weekday.
285  * @stable ICU 51
286  */
287 #define UDAT_ABBR_WEEKDAY               "E"
288 /**
289  * Constant for date skeleton with year, month, weekday, and day.
290  * Used in combinations date + time, date + time + zone, or time + zone.
291  * @stable ICU 4.0
292  */
293 #define UDAT_YEAR_MONTH_WEEKDAY_DAY     "yMMMMEEEEd"
294 /**
295  * Constant for date skeleton with year, abbreviated month, weekday, and day.
296  * Used in combinations date + time, date + time + zone, or time + zone.
297  * @stable ICU 4.0
298  */
299 #define UDAT_YEAR_ABBR_MONTH_WEEKDAY_DAY "yMMMEd"
300 /**
301  * Constant for date skeleton with year, numeric month, weekday, and day.
302  * Used in combinations date + time, date + time + zone, or time + zone.
303  * @stable ICU 4.0
304  */
305 #define UDAT_YEAR_NUM_MONTH_WEEKDAY_DAY "yMEd"
306 /**
307  * Constant for date skeleton with long month and day.
308  * Used in combinations date + time, date + time + zone, or time + zone.
309  * @stable ICU 4.0
310  */
311 #define UDAT_MONTH_DAY                  "MMMMd"
312 /**
313  * Constant for date skeleton with abbreviated month and day.
314  * Used in combinations date + time, date + time + zone, or time + zone.
315  * @stable ICU 4.0
316  */
317 #define UDAT_ABBR_MONTH_DAY             "MMMd"
318 /**
319  * Constant for date skeleton with numeric month and day.
320  * Used in combinations date + time, date + time + zone, or time + zone.
321  * @stable ICU 4.0
322  */
323 #define UDAT_NUM_MONTH_DAY              "Md"
324 /**
325  * Constant for date skeleton with month, weekday, and day.
326  * Used in combinations date + time, date + time + zone, or time + zone.
327  * @stable ICU 4.0
328  */
329 #define UDAT_MONTH_WEEKDAY_DAY          "MMMMEEEEd"
330 /**
331  * Constant for date skeleton with abbreviated month, weekday, and day.
332  * Used in combinations date + time, date + time + zone, or time + zone.
333  * @stable ICU 4.0
334  */
335 #define UDAT_ABBR_MONTH_WEEKDAY_DAY     "MMMEd"
336 /**
337  * Constant for date skeleton with numeric month, weekday, and day.
338  * Used in combinations date + time, date + time + zone, or time + zone.
339  * @stable ICU 4.0
340  */
341 #define UDAT_NUM_MONTH_WEEKDAY_DAY      "MEd"
342 
343 /* Skeletons for times. */
344 
345 /**
346  * Constant for date skeleton with hour, with the locale's preferred hour format (12 or 24).
347  * @stable ICU 4.0
348  */
349 #define UDAT_HOUR                       "j"
350 /**
351  * Constant for date skeleton with hour in 24-hour presentation.
352  * @stable ICU 51
353  */
354 #define UDAT_HOUR24                     "H"
355 /**
356  * Constant for date skeleton with minute.
357  * @stable ICU 51
358  */
359 #define UDAT_MINUTE                     "m"
360 /**
361  * Constant for date skeleton with hour and minute, with the locale's preferred hour format (12 or 24).
362  * Used in combinations date + time, date + time + zone, or time + zone.
363  * @stable ICU 4.0
364  */
365 #define UDAT_HOUR_MINUTE                "jm"
366 /**
367  * Constant for date skeleton with hour and minute in 24-hour presentation.
368  * Used in combinations date + time, date + time + zone, or time + zone.
369  * @stable ICU 4.0
370  */
371 #define UDAT_HOUR24_MINUTE              "Hm"
372 /**
373  * Constant for date skeleton with second.
374  * @stable ICU 51
375  */
376 #define UDAT_SECOND                     "s"
377 /**
378  * Constant for date skeleton with hour, minute, and second,
379  * with the locale's preferred hour format (12 or 24).
380  * Used in combinations date + time, date + time + zone, or time + zone.
381  * @stable ICU 4.0
382  */
383 #define UDAT_HOUR_MINUTE_SECOND         "jms"
384 /**
385  * Constant for date skeleton with hour, minute, and second in
386  * 24-hour presentation.
387  * Used in combinations date + time, date + time + zone, or time + zone.
388  * @stable ICU 4.0
389  */
390 #define UDAT_HOUR24_MINUTE_SECOND       "Hms"
391 /**
392  * Constant for date skeleton with minute and second.
393  * Used in combinations date + time, date + time + zone, or time + zone.
394  * @stable ICU 4.0
395  */
396 #define UDAT_MINUTE_SECOND              "ms"
397 
398 /* Skeletons for time zones. */
399 
400 /**
401  * Constant for <i>generic location format</i>, such as Los Angeles Time;
402  * used in combinations date + time + zone, or time + zone.
403  * @see <a href="http://unicode.org/reports/tr35/#Date_Format_Patterns">LDML Date Format Patterns</a>
404  * @see <a href="http://unicode.org/reports/tr35/#Time_Zone_Fallback">LDML Time Zone Fallback</a>
405  * @stable ICU 51
406  */
407 #define UDAT_LOCATION_TZ "VVVV"
408 /**
409  * Constant for <i>generic non-location format</i>, such as Pacific Time;
410  * used in combinations date + time + zone, or time + zone.
411  * @see <a href="http://unicode.org/reports/tr35/#Date_Format_Patterns">LDML Date Format Patterns</a>
412  * @see <a href="http://unicode.org/reports/tr35/#Time_Zone_Fallback">LDML Time Zone Fallback</a>
413  * @stable ICU 51
414  */
415 #define UDAT_GENERIC_TZ "vvvv"
416 /**
417  * Constant for <i>generic non-location format</i>, abbreviated if possible, such as PT;
418  * used in combinations date + time + zone, or time + zone.
419  * @see <a href="http://unicode.org/reports/tr35/#Date_Format_Patterns">LDML Date Format Patterns</a>
420  * @see <a href="http://unicode.org/reports/tr35/#Time_Zone_Fallback">LDML Time Zone Fallback</a>
421  * @stable ICU 51
422  */
423 #define UDAT_ABBR_GENERIC_TZ "v"
424 /**
425  * Constant for <i>specific non-location format</i>, such as Pacific Daylight Time;
426  * used in combinations date + time + zone, or time + zone.
427  * @see <a href="http://unicode.org/reports/tr35/#Date_Format_Patterns">LDML Date Format Patterns</a>
428  * @see <a href="http://unicode.org/reports/tr35/#Time_Zone_Fallback">LDML Time Zone Fallback</a>
429  * @stable ICU 51
430  */
431 #define UDAT_SPECIFIC_TZ "zzzz"
432 /**
433  * Constant for <i>specific non-location format</i>, abbreviated if possible, such as PDT;
434  * used in combinations date + time + zone, or time + zone.
435  * @see <a href="http://unicode.org/reports/tr35/#Date_Format_Patterns">LDML Date Format Patterns</a>
436  * @see <a href="http://unicode.org/reports/tr35/#Time_Zone_Fallback">LDML Time Zone Fallback</a>
437  * @stable ICU 51
438  */
439 #define UDAT_ABBR_SPECIFIC_TZ "z"
440 /**
441  * Constant for <i>localized GMT/UTC format</i>, such as GMT+8:00 or HPG-8:00;
442  * used in combinations date + time + zone, or time + zone.
443  * @see <a href="http://unicode.org/reports/tr35/#Date_Format_Patterns">LDML Date Format Patterns</a>
444  * @see <a href="http://unicode.org/reports/tr35/#Time_Zone_Fallback">LDML Time Zone Fallback</a>
445  * @stable ICU 51
446  */
447 #define UDAT_ABBR_UTC_TZ "ZZZZ"
448 
449 /* deprecated skeleton constants */
450 
451 #ifndef U_HIDE_DEPRECATED_API
452 /**
453  * Constant for date skeleton with standalone month.
454  * @deprecated ICU 50 Use UDAT_MONTH instead.
455  */
456 #define UDAT_STANDALONE_MONTH           "LLLL"
457 /**
458  * Constant for date skeleton with standalone abbreviated month.
459  * @deprecated ICU 50 Use UDAT_ABBR_MONTH instead.
460  */
461 #define UDAT_ABBR_STANDALONE_MONTH      "LLL"
462 
463 /**
464  * Constant for date skeleton with hour, minute, and generic timezone.
465  * @deprecated ICU 50 Use instead UDAT_HOUR_MINUTE UDAT_ABBR_GENERIC_TZ or some other timezone presentation.
466  */
467 #define UDAT_HOUR_MINUTE_GENERIC_TZ     "jmv"
468 /**
469  * Constant for date skeleton with hour, minute, and timezone.
470  * @deprecated ICU 50 Use instead UDAT_HOUR_MINUTE UDAT_ABBR_SPECIFIC_TZ or some other timezone presentation.
471  */
472 #define UDAT_HOUR_MINUTE_TZ             "jmz"
473 /**
474  * Constant for date skeleton with hour and generic timezone.
475  * @deprecated ICU 50 Use instead UDAT_HOUR UDAT_ABBR_GENERIC_TZ or some other timezone presentation.
476  */
477 #define UDAT_HOUR_GENERIC_TZ            "jv"
478 /**
479  * Constant for date skeleton with hour and timezone.
480  * @deprecated ICU 50 Use instead UDAT_HOUR UDAT_ABBR_SPECIFIC_TZ or some other timezone presentation.
481  */
482 #define UDAT_HOUR_TZ                    "jz"
483 #endif  /* U_HIDE_DEPRECATED_API */
484 
485 /**
486  * FieldPosition and UFieldPosition selectors for format fields
487  * defined by DateFormat and UDateFormat.
488  * @stable ICU 3.0
489  */
490 typedef enum UDateFormatField {
491     /**
492      * FieldPosition and UFieldPosition selector for 'G' field alignment,
493      * corresponding to the UCAL_ERA field.
494      * @stable ICU 3.0
495      */
496     UDAT_ERA_FIELD = 0,
497 
498     /**
499      * FieldPosition and UFieldPosition selector for 'y' field alignment,
500      * corresponding to the UCAL_YEAR field.
501      * @stable ICU 3.0
502      */
503     UDAT_YEAR_FIELD = 1,
504 
505     /**
506      * FieldPosition and UFieldPosition selector for 'M' field alignment,
507      * corresponding to the UCAL_MONTH field.
508      * @stable ICU 3.0
509      */
510     UDAT_MONTH_FIELD = 2,
511 
512     /**
513      * FieldPosition and UFieldPosition selector for 'd' field alignment,
514      * corresponding to the UCAL_DATE field.
515      * @stable ICU 3.0
516      */
517     UDAT_DATE_FIELD = 3,
518 
519     /**
520      * FieldPosition and UFieldPosition selector for 'k' field alignment,
521      * corresponding to the UCAL_HOUR_OF_DAY field.
522      * UDAT_HOUR_OF_DAY1_FIELD is used for the one-based 24-hour clock.
523      * For example, 23:59 + 01:00 results in 24:59.
524      * @stable ICU 3.0
525      */
526     UDAT_HOUR_OF_DAY1_FIELD = 4,
527 
528     /**
529      * FieldPosition and UFieldPosition selector for 'H' field alignment,
530      * corresponding to the UCAL_HOUR_OF_DAY field.
531      * UDAT_HOUR_OF_DAY0_FIELD is used for the zero-based 24-hour clock.
532      * For example, 23:59 + 01:00 results in 00:59.
533      * @stable ICU 3.0
534      */
535     UDAT_HOUR_OF_DAY0_FIELD = 5,
536 
537     /**
538      * FieldPosition and UFieldPosition selector for 'm' field alignment,
539      * corresponding to the UCAL_MINUTE field.
540      * @stable ICU 3.0
541      */
542     UDAT_MINUTE_FIELD = 6,
543 
544     /**
545      * FieldPosition and UFieldPosition selector for 's' field alignment,
546      * corresponding to the UCAL_SECOND field.
547      * @stable ICU 3.0
548      */
549     UDAT_SECOND_FIELD = 7,
550 
551     /**
552      * FieldPosition and UFieldPosition selector for 'S' field alignment,
553      * corresponding to the UCAL_MILLISECOND field.
554      *
555      * Note: Time formats that use 'S' can display a maximum of three
556      * significant digits for fractional seconds, corresponding to millisecond
557      * resolution and a fractional seconds sub-pattern of SSS. If the
558      * sub-pattern is S or SS, the fractional seconds value will be truncated
559      * (not rounded) to the number of display places specified. If the
560      * fractional seconds sub-pattern is longer than SSS, the additional
561      * display places will be filled with zeros.
562      * @stable ICU 3.0
563      */
564     UDAT_FRACTIONAL_SECOND_FIELD = 8,
565 
566     /**
567      * FieldPosition and UFieldPosition selector for 'E' field alignment,
568      * corresponding to the UCAL_DAY_OF_WEEK field.
569      * @stable ICU 3.0
570      */
571     UDAT_DAY_OF_WEEK_FIELD = 9,
572 
573     /**
574      * FieldPosition and UFieldPosition selector for 'D' field alignment,
575      * corresponding to the UCAL_DAY_OF_YEAR field.
576      * @stable ICU 3.0
577      */
578     UDAT_DAY_OF_YEAR_FIELD = 10,
579 
580     /**
581      * FieldPosition and UFieldPosition selector for 'F' field alignment,
582      * corresponding to the UCAL_DAY_OF_WEEK_IN_MONTH field.
583      * @stable ICU 3.0
584      */
585     UDAT_DAY_OF_WEEK_IN_MONTH_FIELD = 11,
586 
587     /**
588      * FieldPosition and UFieldPosition selector for 'w' field alignment,
589      * corresponding to the UCAL_WEEK_OF_YEAR field.
590      * @stable ICU 3.0
591      */
592     UDAT_WEEK_OF_YEAR_FIELD = 12,
593 
594     /**
595      * FieldPosition and UFieldPosition selector for 'W' field alignment,
596      * corresponding to the UCAL_WEEK_OF_MONTH field.
597      * @stable ICU 3.0
598      */
599     UDAT_WEEK_OF_MONTH_FIELD = 13,
600 
601     /**
602      * FieldPosition and UFieldPosition selector for 'a' field alignment,
603      * corresponding to the UCAL_AM_PM field.
604      * @stable ICU 3.0
605      */
606     UDAT_AM_PM_FIELD = 14,
607 
608     /**
609      * FieldPosition and UFieldPosition selector for 'h' field alignment,
610      * corresponding to the UCAL_HOUR field.
611      * UDAT_HOUR1_FIELD is used for the one-based 12-hour clock.
612      * For example, 11:30 PM + 1 hour results in 12:30 AM.
613      * @stable ICU 3.0
614      */
615     UDAT_HOUR1_FIELD = 15,
616 
617     /**
618      * FieldPosition and UFieldPosition selector for 'K' field alignment,
619      * corresponding to the UCAL_HOUR field.
620      * UDAT_HOUR0_FIELD is used for the zero-based 12-hour clock.
621      * For example, 11:30 PM + 1 hour results in 00:30 AM.
622      * @stable ICU 3.0
623      */
624     UDAT_HOUR0_FIELD = 16,
625 
626     /**
627      * FieldPosition and UFieldPosition selector for 'z' field alignment,
628      * corresponding to the UCAL_ZONE_OFFSET and
629      * UCAL_DST_OFFSET fields.
630      * @stable ICU 3.0
631      */
632     UDAT_TIMEZONE_FIELD = 17,
633 
634     /**
635      * FieldPosition and UFieldPosition selector for 'Y' field alignment,
636      * corresponding to the UCAL_YEAR_WOY field.
637      * @stable ICU 3.0
638      */
639     UDAT_YEAR_WOY_FIELD = 18,
640 
641     /**
642      * FieldPosition and UFieldPosition selector for 'e' field alignment,
643      * corresponding to the UCAL_DOW_LOCAL field.
644      * @stable ICU 3.0
645      */
646     UDAT_DOW_LOCAL_FIELD = 19,
647 
648     /**
649      * FieldPosition and UFieldPosition selector for 'u' field alignment,
650      * corresponding to the UCAL_EXTENDED_YEAR field.
651      * @stable ICU 3.0
652      */
653     UDAT_EXTENDED_YEAR_FIELD = 20,
654 
655     /**
656      * FieldPosition and UFieldPosition selector for 'g' field alignment,
657      * corresponding to the UCAL_JULIAN_DAY field.
658      * @stable ICU 3.0
659      */
660     UDAT_JULIAN_DAY_FIELD = 21,
661 
662     /**
663      * FieldPosition and UFieldPosition selector for 'A' field alignment,
664      * corresponding to the UCAL_MILLISECONDS_IN_DAY field.
665      * @stable ICU 3.0
666      */
667     UDAT_MILLISECONDS_IN_DAY_FIELD = 22,
668 
669     /**
670      * FieldPosition and UFieldPosition selector for 'Z' field alignment,
671      * corresponding to the UCAL_ZONE_OFFSET and
672      * UCAL_DST_OFFSET fields.
673      * @stable ICU 3.0
674      */
675     UDAT_TIMEZONE_RFC_FIELD = 23,
676 
677     /**
678      * FieldPosition and UFieldPosition selector for 'v' field alignment,
679      * corresponding to the UCAL_ZONE_OFFSET field.
680      * @stable ICU 3.4
681      */
682     UDAT_TIMEZONE_GENERIC_FIELD = 24,
683     /**
684      * FieldPosition selector for 'c' field alignment,
685      * corresponding to the {@link #UCAL_DOW_LOCAL} field.
686      * This displays the stand alone day name, if available.
687      * @stable ICU 3.4
688      */
689     UDAT_STANDALONE_DAY_FIELD = 25,
690 
691     /**
692      * FieldPosition selector for 'L' field alignment,
693      * corresponding to the {@link #UCAL_MONTH} field.
694      * This displays the stand alone month name, if available.
695      * @stable ICU 3.4
696      */
697     UDAT_STANDALONE_MONTH_FIELD = 26,
698 
699     /**
700      * FieldPosition selector for "Q" field alignment,
701      * corresponding to quarters. This is implemented
702      * using the {@link #UCAL_MONTH} field. This
703      * displays the quarter.
704      * @stable ICU 3.6
705      */
706     UDAT_QUARTER_FIELD = 27,
707 
708     /**
709      * FieldPosition selector for the "q" field alignment,
710      * corresponding to stand-alone quarters. This is
711      * implemented using the {@link #UCAL_MONTH} field.
712      * This displays the stand-alone quarter.
713      * @stable ICU 3.6
714      */
715     UDAT_STANDALONE_QUARTER_FIELD = 28,
716 
717     /**
718      * FieldPosition and UFieldPosition selector for 'V' field alignment,
719      * corresponding to the UCAL_ZONE_OFFSET field.
720      * @stable ICU 3.8
721      */
722     UDAT_TIMEZONE_SPECIAL_FIELD = 29,
723 
724     /**
725      * FieldPosition selector for "U" field alignment,
726      * corresponding to cyclic year names. This is implemented
727      * using the {@link #UCAL_YEAR} field. This displays
728      * the cyclic year name, if available.
729      * @stable ICU 49
730      */
731     UDAT_YEAR_NAME_FIELD = 30,
732 
733     /**
734      * FieldPosition selector for 'O' field alignment,
735      * corresponding to the UCAL_ZONE_OFFSET and UCAL_DST_OFFSETfields.
736      * This displays the localized GMT format.
737      * @stable ICU 51
738      */
739     UDAT_TIMEZONE_LOCALIZED_GMT_OFFSET_FIELD = 31,
740 
741     /**
742      * FieldPosition selector for 'X' field alignment,
743      * corresponding to the UCAL_ZONE_OFFSET and UCAL_DST_OFFSETfields.
744      * This displays the ISO 8601 local time offset format or UTC indicator ("Z").
745      * @stable ICU 51
746      */
747     UDAT_TIMEZONE_ISO_FIELD = 32,
748 
749     /**
750      * FieldPosition selector for 'x' field alignment,
751      * corresponding to the UCAL_ZONE_OFFSET and UCAL_DST_OFFSET fields.
752      * This displays the ISO 8601 local time offset format.
753      * @stable ICU 51
754      */
755     UDAT_TIMEZONE_ISO_LOCAL_FIELD = 33,
756 
757 #ifndef U_HIDE_INTERNAL_API
758     /**
759      * FieldPosition and UFieldPosition selector for 'r' field alignment,
760      * no directly corresponding UCAL_ field.
761      * @internal ICU 53
762      */
763     UDAT_RELATED_YEAR_FIELD = 34,
764 #endif  /* U_HIDE_INTERNAL_API */
765 
766     /**
767      * FieldPosition selector for 'b' field alignment.
768      * Displays midnight and noon for 12am and 12pm, respectively, if available;
769      * otherwise fall back to AM / PM.
770      * @stable ICU 57
771      */
772     UDAT_AM_PM_MIDNIGHT_NOON_FIELD = 35,
773 
774     /* FieldPosition selector for 'B' field alignment.
775      * Displays flexible day periods, such as "in the morning", if available.
776      * @stable ICU 57
777      */
778     UDAT_FLEXIBLE_DAY_PERIOD_FIELD = 36,
779 
780 #ifndef U_HIDE_INTERNAL_API
781     /**
782      * FieldPosition and UFieldPosition selector for time separator,
783      * no corresponding UCAL_ field. No pattern character is currently
784      * defined for this.
785      * @internal
786      */
787     UDAT_TIME_SEPARATOR_FIELD = 37,
788 #endif  /* U_HIDE_INTERNAL_API */
789 
790 #ifndef U_HIDE_DEPRECATED_API
791     /**
792      * Number of FieldPosition and UFieldPosition selectors for
793      * DateFormat and UDateFormat.
794      * Valid selectors range from 0 to UDAT_FIELD_COUNT-1.
795      * @deprecated ICU 58 The numeric value may change over time, see ICU ticket #12420.
796      */
797     UDAT_FIELD_COUNT = 38
798 #endif  /* U_HIDE_DEPRECATED_API */
799 } UDateFormatField;
800 
801 
802 #ifndef U_HIDE_INTERNAL_API
803 /**
804  * Is a pattern character defined for UDAT_TIME_SEPARATOR_FIELD?
805  * In ICU 55 it was COLON, but that was withdrawn in ICU 56.
806  * @internal ICU 56
807  */
808 #define UDAT_HAS_PATTERN_CHAR_FOR_TIME_SEPARATOR 0
809 #endif /* U_HIDE_INTERNAL_API */
810 
811 
812 /**
813  * Maps from a UDateFormatField to the corresponding UCalendarDateFields.
814  * Note: since the mapping is many-to-one, there is no inverse mapping.
815  * @param field the UDateFormatField.
816  * @return the UCalendarDateField.  This will be UCAL_FIELD_COUNT in case
817  * of error (e.g., the input field is UDAT_FIELD_COUNT).
818  * @stable ICU 4.4
819  */
820 U_CAPI UCalendarDateFields U_EXPORT2
821 udat_toCalendarDateField(UDateFormatField field);
822 
823 
824 /**
825  * Open a new UDateFormat for formatting and parsing dates and times.
826  * A UDateFormat may be used to format dates in calls to {@link #udat_format },
827  * and to parse dates in calls to {@link #udat_parse }.
828  * @param timeStyle The style used to format times; one of UDAT_FULL, UDAT_LONG,
829  * UDAT_MEDIUM, UDAT_SHORT, UDAT_DEFAULT, or UDAT_NONE (relative time styles
830  * are not currently supported).
831  * When the pattern parameter is used, pass in UDAT_PATTERN for both timeStyle and dateStyle.
832  * @param dateStyle The style used to format dates; one of UDAT_FULL, UDAT_LONG,
833  * UDAT_MEDIUM, UDAT_SHORT, UDAT_DEFAULT, UDAT_FULL_RELATIVE, UDAT_LONG_RELATIVE,
834  * UDAT_MEDIUM_RELATIVE, UDAT_SHORT_RELATIVE, or UDAT_NONE.
835  * When the pattern parameter is used, pass in UDAT_PATTERN for both timeStyle and dateStyle.
836  * As currently implemented,
837  * relative date formatting only affects a limited range of calendar days before or
838  * after the current date, based on the CLDR &lt;field type="day"&gt;/&lt;relative&gt; data: For
839  * example, in English, "Yesterday", "Today", and "Tomorrow". Outside of this range,
840  * dates are formatted using the corresponding non-relative style.
841  * @param locale The locale specifying the formatting conventions
842  * @param tzID A timezone ID specifying the timezone to use.  If 0, use
843  * the default timezone.
844  * @param tzIDLength The length of tzID, or -1 if null-terminated.
845  * @param pattern A pattern specifying the format to use.
846  * @param patternLength The number of characters in the pattern, or -1 if null-terminated.
847  * @param status A pointer to an UErrorCode to receive any errors
848  * @return A pointer to a UDateFormat to use for formatting dates and times, or 0 if
849  * an error occurred.
850  * @stable ICU 2.0
851  */
852 U_CAPI UDateFormat* U_EXPORT2
853 udat_open(UDateFormatStyle  timeStyle,
854           UDateFormatStyle  dateStyle,
855           const char        *locale,
856           const UChar       *tzID,
857           int32_t           tzIDLength,
858           const UChar       *pattern,
859           int32_t           patternLength,
860           UErrorCode        *status);
861 
862 
863 /**
864 * Close a UDateFormat.
865 * Once closed, a UDateFormat may no longer be used.
866 * @param format The formatter to close.
867 * @stable ICU 2.0
868 */
869 U_CAPI void U_EXPORT2
870 udat_close(UDateFormat* format);
871 
872 
873 /**
874  * DateFormat boolean attributes
875  *
876  * @stable ICU 53
877  */
878 typedef enum UDateFormatBooleanAttribute {
879    /**
880      * indicates whether whitespace is allowed. Includes trailing dot tolerance.
881      * @stable ICU 53
882      */
883     UDAT_PARSE_ALLOW_WHITESPACE = 0,
884     /**
885      * indicates tolerance of numeric data when String data may be assumed. eg: UDAT_YEAR_NAME_FIELD,
886      * UDAT_STANDALONE_MONTH_FIELD, UDAT_DAY_OF_WEEK_FIELD
887      * @stable ICU 53
888      */
889     UDAT_PARSE_ALLOW_NUMERIC = 1,
890     /**
891      * indicates tolerance of a partial literal match
892      * e.g. accepting "--mon-02-march-2011" for a pattern of "'--: 'EEE-WW-MMMM-yyyy"
893      * @stable ICU 56
894      */
895     UDAT_PARSE_PARTIAL_LITERAL_MATCH = 2,
896     /**
897      * indicates tolerance of pattern mismatch between input data and specified format pattern.
898      * e.g. accepting "September" for a month pattern of MMM ("Sep")
899      * @stable ICU 56
900      */
901     UDAT_PARSE_MULTIPLE_PATTERNS_FOR_MATCH = 3,
902 
903     /* Do not conditionalize the following with #ifndef U_HIDE_DEPRECATED_API,
904      * it is needed for layout of DateFormat object. */
905     /**
906      * One more than the highest normal UDateFormatBooleanAttribute value.
907      * @deprecated ICU 58 The numeric value may change over time, see ICU ticket #12420.
908      */
909     UDAT_BOOLEAN_ATTRIBUTE_COUNT = 4
910 } UDateFormatBooleanAttribute;
911 
912 /**
913  * Get a boolean attribute associated with a UDateFormat.
914  * An example would be a true value for a key of UDAT_PARSE_ALLOW_WHITESPACE indicating allowing whitespace leniency.
915  * If the formatter does not understand the attribute, -1 is returned.
916  * @param fmt The formatter to query.
917  * @param attr The attribute to query; e.g. UDAT_PARSE_ALLOW_WHITESPACE.
918  * @param status A pointer to an UErrorCode to receive any errors
919  * @return The value of attr.
920  * @stable ICU 53
921  */
922 U_CAPI UBool U_EXPORT2
923 udat_getBooleanAttribute(const UDateFormat* fmt, UDateFormatBooleanAttribute attr, UErrorCode* status);
924 
925 /**
926  * Set a boolean attribute associated with a UDateFormat.
927  * An example of a boolean attribute is parse leniency control.  If the formatter does not understand
928  * the attribute, the call is ignored.
929  * @param fmt The formatter to set.
930  * @param attr The attribute to set; one of UDAT_PARSE_ALLOW_WHITESPACE or UDAT_PARSE_ALLOW_NUMERIC
931  * @param newValue The new value of attr.
932  * @param status A pointer to an UErrorCode to receive any errors
933  * @stable ICU 53
934  */
935 U_CAPI void U_EXPORT2
936 udat_setBooleanAttribute(UDateFormat *fmt, UDateFormatBooleanAttribute attr, UBool newValue, UErrorCode* status);
937 
938 
939 
940 #if U_SHOW_CPLUSPLUS_API
941 
942 U_NAMESPACE_BEGIN
943 
944 /**
945  * \class LocalUDateFormatPointer
946  * "Smart pointer" class, closes a UDateFormat via udat_close().
947  * For most methods see the LocalPointerBase base class.
948  *
949  * @see LocalPointerBase
950  * @see LocalPointer
951  * @stable ICU 4.4
952  */
953 U_DEFINE_LOCAL_OPEN_POINTER(LocalUDateFormatPointer, UDateFormat, udat_close);
954 
955 U_NAMESPACE_END
956 
957 #endif
958 
959 /**
960  * Open a copy of a UDateFormat.
961  * This function performs a deep copy.
962  * @param fmt The format to copy
963  * @param status A pointer to an UErrorCode to receive any errors.
964  * @return A pointer to a UDateFormat identical to fmt.
965  * @stable ICU 2.0
966  */
967 U_CAPI UDateFormat* U_EXPORT2
968 udat_clone(const UDateFormat *fmt,
969        UErrorCode *status);
970 
971 /**
972 * Format a date using a UDateFormat.
973 * The date will be formatted using the conventions specified in {@link #udat_open }
974 * @param format The formatter to use
975 * @param dateToFormat The date to format
976 * @param result A pointer to a buffer to receive the formatted number.
977 * @param resultLength The maximum size of result.
978 * @param position A pointer to a UFieldPosition.  On input, position->field
979 * is read.  On output, position->beginIndex and position->endIndex indicate
980 * the beginning and ending indices of field number position->field, if such
981 * a field exists.  This parameter may be NULL, in which case no field
982 * position data is returned.
983 * @param status A pointer to an UErrorCode to receive any errors
984 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
985 * @see udat_parse
986 * @see UFieldPosition
987 * @stable ICU 2.0
988 */
989 U_CAPI int32_t U_EXPORT2
990 udat_format(    const    UDateFormat*    format,
991                         UDate           dateToFormat,
992                         UChar*          result,
993                         int32_t         resultLength,
994                         UFieldPosition* position,
995                         UErrorCode*     status);
996 
997 /**
998 * Format a date using an UDateFormat.
999 * The date will be formatted using the conventions specified in {@link #udat_open }
1000 * @param format The formatter to use
1001 * @param calendar The calendar to format. The calendar instance might be
1002 *                 mutated if fields are not yet fully calculated, though
1003 *                 the function won't change the logical date and time held
1004 *                 by the instance.
1005 * @param result A pointer to a buffer to receive the formatted number.
1006 * @param capacity The maximum size of result.
1007 * @param position A pointer to a UFieldPosition.  On input, position->field
1008 * is read.  On output, position->beginIndex and position->endIndex indicate
1009 * the beginning and ending indices of field number position->field, if such
1010 * a field exists.  This parameter may be NULL, in which case no field
1011 * position data is returned.
1012 * @param status A pointer to an UErrorCode to receive any errors
1013 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
1014 * @see udat_format
1015 * @see udat_parseCalendar
1016 * @see UFieldPosition
1017 * @stable ICU 55
1018 */
1019 U_CAPI int32_t U_EXPORT2
1020 udat_formatCalendar(    const UDateFormat*  format,
1021                         UCalendar*      calendar,
1022                         UChar*          result,
1023                         int32_t         capacity,
1024                         UFieldPosition* position,
1025                         UErrorCode*     status);
1026 
1027 /**
1028 * Format a date using a UDateFormat.
1029 * The date will be formatted using the conventions specified in {@link #udat_open}
1030 * @param format
1031 *          The formatter to use
1032 * @param dateToFormat
1033 *          The date to format
1034 * @param result
1035 *          A pointer to a buffer to receive the formatted number.
1036 * @param resultLength
1037 *          The maximum size of result.
1038 * @param fpositer
1039 *          A pointer to a UFieldPositionIterator created by {@link #ufieldpositer_open}
1040 *          (may be NULL if field position information is not needed). Any
1041 *          iteration information already present in the UFieldPositionIterator
1042 *          will be deleted, and the iterator will be reset to apply to the
1043 *          fields in the formatted string created by this function call; the
1044 *          field values provided by {@link #ufieldpositer_next} will be from the
1045 *          UDateFormatField enum.
1046 * @param status
1047 *          A pointer to a UErrorCode to receive any errors
1048 * @return
1049 *          The total buffer size needed; if greater than resultLength, the output was truncated.
1050 * @see udat_parse
1051 * @see UFieldPositionIterator
1052 * @stable ICU 55
1053 */
1054 U_CAPI int32_t U_EXPORT2
1055 udat_formatForFields(   const UDateFormat* format,
1056                         UDate           dateToFormat,
1057                         UChar*          result,
1058                         int32_t         resultLength,
1059                         UFieldPositionIterator* fpositer,
1060                         UErrorCode*     status);
1061 
1062 /**
1063 * Format a date using a UDateFormat.
1064 * The date will be formatted using the conventions specified in {@link #udat_open }
1065 * @param format
1066 *          The formatter to use
1067 * @param calendar
1068 *          The calendar to format. The calendar instance might be mutated if fields
1069 *          are not yet fully calculated, though the function won't change the logical
1070 *          date and time held by the instance.
1071 * @param result
1072 *          A pointer to a buffer to receive the formatted number.
1073 * @param capacity
1074 *          The maximum size of result.
1075 * @param fpositer
1076 *          A pointer to a UFieldPositionIterator created by {@link #ufieldpositer_open}
1077 *          (may be NULL if field position information is not needed). Any
1078 *          iteration information already present in the UFieldPositionIterator
1079 *          will be deleted, and the iterator will be reset to apply to the
1080 *          fields in the formatted string created by this function call; the
1081 *          field values provided by {@link #ufieldpositer_next} will be from the
1082 *          UDateFormatField enum.
1083 * @param status
1084 *          A pointer to a UErrorCode to receive any errors
1085 * @return
1086 *          The total buffer size needed; if greater than resultLength, the output was truncated.
1087 * @see udat_format
1088 * @see udat_parseCalendar
1089 * @see UFieldPositionIterator
1090 * @stable ICU 55
1091 */
1092 U_CAPI int32_t U_EXPORT2
1093 udat_formatCalendarForFields( const UDateFormat* format,
1094                         UCalendar*      calendar,
1095                         UChar*          result,
1096                         int32_t         capacity,
1097                         UFieldPositionIterator* fpositer,
1098                         UErrorCode*     status);
1099 
1100 
1101 /**
1102 * Parse a string into an date/time using a UDateFormat.
1103 * The date will be parsed using the conventions specified in {@link #udat_open }.
1104 * <P>
1105 * Note that the normal date formats associated with some calendars - such
1106 * as the Chinese lunar calendar - do not specify enough fields to enable
1107 * dates to be parsed unambiguously. In the case of the Chinese lunar
1108 * calendar, while the year within the current 60-year cycle is specified,
1109 * the number of such cycles since the start date of the calendar (in the
1110 * UCAL_ERA field of the UCalendar object) is not normally part of the format,
1111 * and parsing may assume the wrong era. For cases such as this it is
1112 * recommended that clients parse using udat_parseCalendar with the UCalendar
1113 * passed in set to the current date, or to a date within the era/cycle that
1114 * should be assumed if absent in the format.
1115 *
1116 * @param format The formatter to use.
1117 * @param text The text to parse.
1118 * @param textLength The length of text, or -1 if null-terminated.
1119 * @param parsePos If not 0, on input a pointer to an integer specifying the offset at which
1120 * to begin parsing.  If not 0, on output the offset at which parsing ended.
1121 * @param status A pointer to an UErrorCode to receive any errors
1122 * @return The value of the parsed date/time
1123 * @see udat_format
1124 * @stable ICU 2.0
1125 */
1126 U_CAPI UDate U_EXPORT2
1127 udat_parse(const    UDateFormat*    format,
1128            const    UChar*          text,
1129                     int32_t         textLength,
1130                     int32_t         *parsePos,
1131                     UErrorCode      *status);
1132 
1133 /**
1134 * Parse a string into an date/time using a UDateFormat.
1135 * The date will be parsed using the conventions specified in {@link #udat_open }.
1136 * @param format The formatter to use.
1137 * @param calendar A calendar set on input to the date and time to be used for
1138 *                 missing values in the date/time string being parsed, and set
1139 *                 on output to the parsed date/time. When the calendar type is
1140 *                 different from the internal calendar held by the UDateFormat
1141 *                 instance, the internal calendar will be cloned to a work
1142 *                 calendar set to the same milliseconds and time zone as this
1143 *                 calendar parameter, field values will be parsed based on the
1144 *                 work calendar, then the result (milliseconds and time zone)
1145 *                 will be set in this calendar.
1146 * @param text The text to parse.
1147 * @param textLength The length of text, or -1 if null-terminated.
1148 * @param parsePos If not 0, on input a pointer to an integer specifying the offset at which
1149 * to begin parsing.  If not 0, on output the offset at which parsing ended.
1150 * @param status A pointer to an UErrorCode to receive any errors
1151 * @see udat_format
1152 * @stable ICU 2.0
1153 */
1154 U_CAPI void U_EXPORT2
1155 udat_parseCalendar(const    UDateFormat*    format,
1156                             UCalendar*      calendar,
1157                    const    UChar*          text,
1158                             int32_t         textLength,
1159                             int32_t         *parsePos,
1160                             UErrorCode      *status);
1161 
1162 /**
1163 * Determine if an UDateFormat will perform lenient parsing.
1164 * With lenient parsing, the parser may use heuristics to interpret inputs that do not
1165 * precisely match the pattern. With strict parsing, inputs must match the pattern.
1166 * @param fmt The formatter to query
1167 * @return TRUE if fmt is set to perform lenient parsing, FALSE otherwise.
1168 * @see udat_setLenient
1169 * @stable ICU 2.0
1170 */
1171 U_CAPI UBool U_EXPORT2
1172 udat_isLenient(const UDateFormat* fmt);
1173 
1174 /**
1175 * Specify whether an UDateFormat will perform lenient parsing.
1176 * With lenient parsing, the parser may use heuristics to interpret inputs that do not
1177 * precisely match the pattern. With strict parsing, inputs must match the pattern.
1178 * @param fmt The formatter to set
1179 * @param isLenient TRUE if fmt should perform lenient parsing, FALSE otherwise.
1180 * @see dat_isLenient
1181 * @stable ICU 2.0
1182 */
1183 U_CAPI void U_EXPORT2
1184 udat_setLenient(    UDateFormat*    fmt,
1185                     UBool          isLenient);
1186 
1187 /**
1188 * Get the UCalendar associated with an UDateFormat.
1189 * A UDateFormat uses a UCalendar to convert a raw value to, for example,
1190 * the day of the week.
1191 * @param fmt The formatter to query.
1192 * @return A pointer to the UCalendar used by fmt.
1193 * @see udat_setCalendar
1194 * @stable ICU 2.0
1195 */
1196 U_CAPI const UCalendar* U_EXPORT2
1197 udat_getCalendar(const UDateFormat* fmt);
1198 
1199 /**
1200 * Set the UCalendar associated with an UDateFormat.
1201 * A UDateFormat uses a UCalendar to convert a raw value to, for example,
1202 * the day of the week.
1203 * @param fmt The formatter to set.
1204 * @param calendarToSet A pointer to an UCalendar to be used by fmt.
1205 * @see udat_setCalendar
1206 * @stable ICU 2.0
1207 */
1208 U_CAPI void U_EXPORT2
1209 udat_setCalendar(            UDateFormat*    fmt,
1210                     const   UCalendar*      calendarToSet);
1211 
1212 /**
1213 * Get the UNumberFormat associated with an UDateFormat.
1214 * A UDateFormat uses a UNumberFormat to format numbers within a date,
1215 * for example the day number.
1216 * @param fmt The formatter to query.
1217 * @return A pointer to the UNumberFormat used by fmt to format numbers.
1218 * @see udat_setNumberFormat
1219 * @stable ICU 2.0
1220 */
1221 U_CAPI const UNumberFormat* U_EXPORT2
1222 udat_getNumberFormat(const UDateFormat* fmt);
1223 
1224 /**
1225 * Get the UNumberFormat for specific field associated with an UDateFormat.
1226 * For example: 'y' for year and 'M' for month
1227 * @param fmt The formatter to query.
1228 * @param field the field to query
1229 * @return A pointer to the UNumberFormat used by fmt to format field numbers.
1230 * @see udat_setNumberFormatForField
1231 * @stable ICU 54
1232 */
1233 U_CAPI const UNumberFormat* U_EXPORT2
1234 udat_getNumberFormatForField(const UDateFormat* fmt, UChar field);
1235 
1236 /**
1237 * Set the UNumberFormat for specific field associated with an UDateFormat.
1238 * It can be a single field like: "y"(year) or "M"(month)
1239 * It can be several field combined together: "yM"(year and month)
1240 * Note:
1241 * 1 symbol field is enough for multiple symbol field (so "y" will override "yy", "yyy")
1242 * If the field is not numeric, then override has no effect (like "MMM" will use abbreviation, not numerical field)
1243 *
1244 * @param fields the fields to set
1245 * @param fmt The formatter to set.
1246 * @param numberFormatToSet A pointer to the UNumberFormat to be used by fmt to format numbers.
1247 * @param status error code passed around (memory allocation or invalid fields)
1248 * @see udat_getNumberFormatForField
1249 * @stable ICU 54
1250 */
1251 U_CAPI void U_EXPORT2
1252 udat_adoptNumberFormatForFields(  UDateFormat* fmt,
1253                             const UChar* fields,
1254                                   UNumberFormat*  numberFormatToSet,
1255                                   UErrorCode* status);
1256 /**
1257 * Set the UNumberFormat associated with an UDateFormat.
1258 * A UDateFormat uses a UNumberFormat to format numbers within a date,
1259 * for example the day number.
1260 * This method also clears per field NumberFormat instances previously
1261 * set by {@see udat_setNumberFormatForField}
1262 * @param fmt The formatter to set.
1263 * @param numberFormatToSet A pointer to the UNumberFormat to be used by fmt to format numbers.
1264 * @see udat_getNumberFormat
1265 * @see udat_setNumberFormatForField
1266 * @stable ICU 2.0
1267 */
1268 U_CAPI void U_EXPORT2
1269 udat_setNumberFormat(            UDateFormat*    fmt,
1270                         const   UNumberFormat*  numberFormatToSet);
1271 /**
1272 * Adopt the UNumberFormat associated with an UDateFormat.
1273 * A UDateFormat uses a UNumberFormat to format numbers within a date,
1274 * for example the day number.
1275 * @param fmt The formatter to set.
1276 * @param numberFormatToAdopt A pointer to the UNumberFormat to be used by fmt to format numbers.
1277 * @see udat_getNumberFormat
1278 * @stable ICU 54
1279 */
1280 U_CAPI void U_EXPORT2
1281 udat_adoptNumberFormat(            UDateFormat*    fmt,
1282                                    UNumberFormat*  numberFormatToAdopt);
1283 /**
1284 * Get a locale for which date/time formatting patterns are available.
1285 * A UDateFormat in a locale returned by this function will perform the correct
1286 * formatting and parsing for the locale.
1287 * @param localeIndex The index of the desired locale.
1288 * @return A locale for which date/time formatting patterns are available, or 0 if none.
1289 * @see udat_countAvailable
1290 * @stable ICU 2.0
1291 */
1292 U_CAPI const char* U_EXPORT2
1293 udat_getAvailable(int32_t localeIndex);
1294 
1295 /**
1296 * Determine how many locales have date/time  formatting patterns available.
1297 * This function is most useful as determining the loop ending condition for
1298 * calls to {@link #udat_getAvailable }.
1299 * @return The number of locales for which date/time formatting patterns are available.
1300 * @see udat_getAvailable
1301 * @stable ICU 2.0
1302 */
1303 U_CAPI int32_t U_EXPORT2
1304 udat_countAvailable(void);
1305 
1306 /**
1307 * Get the year relative to which all 2-digit years are interpreted.
1308 * For example, if the 2-digit start year is 2100, the year 99 will be
1309 * interpreted as 2199.
1310 * @param fmt The formatter to query.
1311 * @param status A pointer to an UErrorCode to receive any errors
1312 * @return The year relative to which all 2-digit years are interpreted.
1313 * @see udat_Set2DigitYearStart
1314 * @stable ICU 2.0
1315 */
1316 U_CAPI UDate U_EXPORT2
1317 udat_get2DigitYearStart(    const   UDateFormat     *fmt,
1318                                     UErrorCode      *status);
1319 
1320 /**
1321 * Set the year relative to which all 2-digit years will be interpreted.
1322 * For example, if the 2-digit start year is 2100, the year 99 will be
1323 * interpreted as 2199.
1324 * @param fmt The formatter to set.
1325 * @param d The year relative to which all 2-digit years will be interpreted.
1326 * @param status A pointer to an UErrorCode to receive any errors
1327 * @see udat_Set2DigitYearStart
1328 * @stable ICU 2.0
1329 */
1330 U_CAPI void U_EXPORT2
1331 udat_set2DigitYearStart(    UDateFormat     *fmt,
1332                             UDate           d,
1333                             UErrorCode      *status);
1334 
1335 /**
1336 * Extract the pattern from a UDateFormat.
1337 * The pattern will follow the pattern syntax rules.
1338 * @param fmt The formatter to query.
1339 * @param localized TRUE if the pattern should be localized, FALSE otherwise.
1340 * @param result A pointer to a buffer to receive the pattern.
1341 * @param resultLength The maximum size of result.
1342 * @param status A pointer to an UErrorCode to receive any errors
1343 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
1344 * @see udat_applyPattern
1345 * @stable ICU 2.0
1346 */
1347 U_CAPI int32_t U_EXPORT2
1348 udat_toPattern(    const   UDateFormat     *fmt,
1349                         UBool          localized,
1350                         UChar           *result,
1351                         int32_t         resultLength,
1352                         UErrorCode      *status);
1353 
1354 /**
1355 * Set the pattern used by an UDateFormat.
1356 * The pattern should follow the pattern syntax rules.
1357 * @param format The formatter to set.
1358 * @param localized TRUE if the pattern is localized, FALSE otherwise.
1359 * @param pattern The new pattern
1360 * @param patternLength The length of pattern, or -1 if null-terminated.
1361 * @see udat_toPattern
1362 * @stable ICU 2.0
1363 */
1364 U_CAPI void U_EXPORT2
1365 udat_applyPattern(            UDateFormat     *format,
1366                             UBool          localized,
1367                     const   UChar           *pattern,
1368                             int32_t         patternLength);
1369 
1370 /**
1371  * The possible types of date format symbols
1372  * @stable ICU 2.6
1373  */
1374 typedef enum UDateFormatSymbolType {
1375     /** The era names, for example AD */
1376     UDAT_ERAS,
1377     /** The month names, for example February */
1378     UDAT_MONTHS,
1379     /** The short month names, for example Feb. */
1380     UDAT_SHORT_MONTHS,
1381     /** The CLDR-style format "wide" weekday names, for example Monday */
1382     UDAT_WEEKDAYS,
1383     /**
1384      * The CLDR-style format "abbreviated" (not "short") weekday names, for example "Mon."
1385      * For the CLDR-style format "short" weekday names, use UDAT_SHORTER_WEEKDAYS.
1386      */
1387     UDAT_SHORT_WEEKDAYS,
1388     /** The AM/PM names, for example AM */
1389     UDAT_AM_PMS,
1390     /** The localized characters */
1391     UDAT_LOCALIZED_CHARS,
1392     /** The long era names, for example Anno Domini */
1393     UDAT_ERA_NAMES,
1394     /** The narrow month names, for example F */
1395     UDAT_NARROW_MONTHS,
1396     /** The CLDR-style format "narrow" weekday names, for example "M" */
1397     UDAT_NARROW_WEEKDAYS,
1398     /** Standalone context versions of months */
1399     UDAT_STANDALONE_MONTHS,
1400     UDAT_STANDALONE_SHORT_MONTHS,
1401     UDAT_STANDALONE_NARROW_MONTHS,
1402     /** The CLDR-style stand-alone "wide" weekday names */
1403     UDAT_STANDALONE_WEEKDAYS,
1404     /**
1405      * The CLDR-style stand-alone "abbreviated" (not "short") weekday names.
1406      * For the CLDR-style stand-alone "short" weekday names, use UDAT_STANDALONE_SHORTER_WEEKDAYS.
1407      */
1408     UDAT_STANDALONE_SHORT_WEEKDAYS,
1409     /** The CLDR-style stand-alone "narrow" weekday names */
1410     UDAT_STANDALONE_NARROW_WEEKDAYS,
1411     /** The quarters, for example 1st Quarter */
1412     UDAT_QUARTERS,
1413     /** The short quarter names, for example Q1 */
1414     UDAT_SHORT_QUARTERS,
1415     /** Standalone context versions of quarters */
1416     UDAT_STANDALONE_QUARTERS,
1417     UDAT_STANDALONE_SHORT_QUARTERS,
1418     /**
1419      * The CLDR-style short weekday names, e.g. "Su", Mo", etc.
1420      * These are named "SHORTER" to contrast with the constants using _SHORT_
1421      * above, which actually get the CLDR-style *abbreviated* versions of the
1422      * corresponding names.
1423      * @stable ICU 51
1424      */
1425     UDAT_SHORTER_WEEKDAYS,
1426     /**
1427      * Standalone version of UDAT_SHORTER_WEEKDAYS.
1428      * @stable ICU 51
1429      */
1430     UDAT_STANDALONE_SHORTER_WEEKDAYS,
1431     /**
1432      * Cyclic year names (only supported for some calendars, and only for FORMAT usage;
1433      * udat_setSymbols not supported for UDAT_CYCLIC_YEARS_WIDE)
1434      * @stable ICU 54
1435      */
1436     UDAT_CYCLIC_YEARS_WIDE,
1437     /**
1438      * Cyclic year names (only supported for some calendars, and only for FORMAT usage)
1439      * @stable ICU 54
1440      */
1441     UDAT_CYCLIC_YEARS_ABBREVIATED,
1442     /**
1443      * Cyclic year names (only supported for some calendars, and only for FORMAT usage;
1444      * udat_setSymbols not supported for UDAT_CYCLIC_YEARS_NARROW)
1445      * @stable ICU 54
1446      */
1447     UDAT_CYCLIC_YEARS_NARROW,
1448     /**
1449      * Calendar zodiac  names (only supported for some calendars, and only for FORMAT usage;
1450      * udat_setSymbols not supported for UDAT_ZODIAC_NAMES_WIDE)
1451      * @stable ICU 54
1452      */
1453     UDAT_ZODIAC_NAMES_WIDE,
1454     /**
1455      * Calendar zodiac  names (only supported for some calendars, and only for FORMAT usage)
1456      * @stable ICU 54
1457      */
1458     UDAT_ZODIAC_NAMES_ABBREVIATED,
1459     /**
1460      * Calendar zodiac  names (only supported for some calendars, and only for FORMAT usage;
1461      * udat_setSymbols not supported for UDAT_ZODIAC_NAMES_NARROW)
1462      * @stable ICU 54
1463      */
1464     UDAT_ZODIAC_NAMES_NARROW
1465 } UDateFormatSymbolType;
1466 
1467 struct UDateFormatSymbols;
1468 /** Date format symbols.
1469  *  For usage in C programs.
1470  *  @stable ICU 2.6
1471  */
1472 typedef struct UDateFormatSymbols UDateFormatSymbols;
1473 
1474 /**
1475 * Get the symbols associated with an UDateFormat.
1476 * The symbols are what a UDateFormat uses to represent locale-specific data,
1477 * for example month or day names.
1478 * @param fmt The formatter to query.
1479 * @param type The type of symbols to get.  One of UDAT_ERAS, UDAT_MONTHS, UDAT_SHORT_MONTHS,
1480 * UDAT_WEEKDAYS, UDAT_SHORT_WEEKDAYS, UDAT_AM_PMS, or UDAT_LOCALIZED_CHARS
1481 * @param symbolIndex The desired symbol of type type.
1482 * @param result A pointer to a buffer to receive the pattern.
1483 * @param resultLength The maximum size of result.
1484 * @param status A pointer to an UErrorCode to receive any errors
1485 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
1486 * @see udat_countSymbols
1487 * @see udat_setSymbols
1488 * @stable ICU 2.0
1489 */
1490 U_CAPI int32_t U_EXPORT2
1491 udat_getSymbols(const   UDateFormat             *fmt,
1492                         UDateFormatSymbolType   type,
1493                         int32_t                 symbolIndex,
1494                         UChar                   *result,
1495                         int32_t                 resultLength,
1496                         UErrorCode              *status);
1497 
1498 /**
1499 * Count the number of particular symbols for an UDateFormat.
1500 * This function is most useful as for detemining the loop termination condition
1501 * for calls to {@link #udat_getSymbols }.
1502 * @param fmt The formatter to query.
1503 * @param type The type of symbols to count.  One of UDAT_ERAS, UDAT_MONTHS, UDAT_SHORT_MONTHS,
1504 * UDAT_WEEKDAYS, UDAT_SHORT_WEEKDAYS, UDAT_AM_PMS, or UDAT_LOCALIZED_CHARS
1505 * @return The number of symbols of type type.
1506 * @see udat_getSymbols
1507 * @see udat_setSymbols
1508 * @stable ICU 2.0
1509 */
1510 U_CAPI int32_t U_EXPORT2
1511 udat_countSymbols(    const    UDateFormat                *fmt,
1512                             UDateFormatSymbolType    type);
1513 
1514 /**
1515 * Set the symbols associated with an UDateFormat.
1516 * The symbols are what a UDateFormat uses to represent locale-specific data,
1517 * for example month or day names.
1518 * @param format The formatter to set
1519 * @param type The type of symbols to set.  One of UDAT_ERAS, UDAT_MONTHS, UDAT_SHORT_MONTHS,
1520 * UDAT_WEEKDAYS, UDAT_SHORT_WEEKDAYS, UDAT_AM_PMS, or UDAT_LOCALIZED_CHARS
1521 * @param symbolIndex The index of the symbol to set of type type.
1522 * @param value The new value
1523 * @param valueLength The length of value, or -1 if null-terminated
1524 * @param status A pointer to an UErrorCode to receive any errors
1525 * @see udat_getSymbols
1526 * @see udat_countSymbols
1527 * @stable ICU 2.0
1528 */
1529 U_CAPI void U_EXPORT2
1530 udat_setSymbols(    UDateFormat             *format,
1531                     UDateFormatSymbolType   type,
1532                     int32_t                 symbolIndex,
1533                     UChar                   *value,
1534                     int32_t                 valueLength,
1535                     UErrorCode              *status);
1536 
1537 /**
1538  * Get the locale for this date format object.
1539  * You can choose between valid and actual locale.
1540  * @param fmt The formatter to get the locale from
1541  * @param type type of the locale we're looking for (valid or actual)
1542  * @param status error code for the operation
1543  * @return the locale name
1544  * @stable ICU 2.8
1545  */
1546 U_CAPI const char* U_EXPORT2
1547 udat_getLocaleByType(const UDateFormat *fmt,
1548                      ULocDataLocaleType type,
1549                      UErrorCode* status);
1550 
1551 /**
1552  * Set a particular UDisplayContext value in the formatter, such as
1553  * UDISPCTX_CAPITALIZATION_FOR_STANDALONE.
1554  * @param fmt The formatter for which to set a UDisplayContext value.
1555  * @param value The UDisplayContext value to set.
1556  * @param status A pointer to an UErrorCode to receive any errors
1557  * @stable ICU 51
1558  */
1559 U_CAPI void U_EXPORT2
1560 udat_setContext(UDateFormat* fmt, UDisplayContext value, UErrorCode* status);
1561 
1562 /**
1563  * Get the formatter's UDisplayContext value for the specified UDisplayContextType,
1564  * such as UDISPCTX_TYPE_CAPITALIZATION.
1565  * @param fmt The formatter to query.
1566  * @param type The UDisplayContextType whose value to return
1567  * @param status A pointer to an UErrorCode to receive any errors
1568  * @return The UDisplayContextValue for the specified type.
1569  * @stable ICU 53
1570  */
1571 U_CAPI UDisplayContext U_EXPORT2
1572 udat_getContext(const UDateFormat* fmt, UDisplayContextType type, UErrorCode* status);
1573 
1574 #ifndef U_HIDE_INTERNAL_API
1575 /**
1576 * Extract the date pattern from a UDateFormat set for relative date formatting.
1577 * The pattern will follow the pattern syntax rules.
1578 * @param fmt The formatter to query.
1579 * @param result A pointer to a buffer to receive the pattern.
1580 * @param resultLength The maximum size of result.
1581 * @param status A pointer to a UErrorCode to receive any errors
1582 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
1583 * @see udat_applyPatternRelative
1584 * @internal ICU 4.2 technology preview
1585 */
1586 U_INTERNAL int32_t U_EXPORT2
1587 udat_toPatternRelativeDate(const UDateFormat *fmt,
1588                            UChar             *result,
1589                            int32_t           resultLength,
1590                            UErrorCode        *status);
1591 
1592 /**
1593 * Extract the time pattern from a UDateFormat set for relative date formatting.
1594 * The pattern will follow the pattern syntax rules.
1595 * @param fmt The formatter to query.
1596 * @param result A pointer to a buffer to receive the pattern.
1597 * @param resultLength The maximum size of result.
1598 * @param status A pointer to a UErrorCode to receive any errors
1599 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
1600 * @see udat_applyPatternRelative
1601 * @internal ICU 4.2 technology preview
1602 */
1603 U_INTERNAL int32_t U_EXPORT2
1604 udat_toPatternRelativeTime(const UDateFormat *fmt,
1605                            UChar             *result,
1606                            int32_t           resultLength,
1607                            UErrorCode        *status);
1608 
1609 /**
1610 * Set the date & time patterns used by a UDateFormat set for relative date formatting.
1611 * The patterns should follow the pattern syntax rules.
1612 * @param format The formatter to set.
1613 * @param datePattern The new date pattern
1614 * @param datePatternLength The length of datePattern, or -1 if null-terminated.
1615 * @param timePattern The new time pattern
1616 * @param timePatternLength The length of timePattern, or -1 if null-terminated.
1617 * @param status A pointer to a UErrorCode to receive any errors
1618 * @see udat_toPatternRelativeDate, udat_toPatternRelativeTime
1619 * @internal ICU 4.2 technology preview
1620 */
1621 U_INTERNAL void U_EXPORT2
1622 udat_applyPatternRelative(UDateFormat *format,
1623                           const UChar *datePattern,
1624                           int32_t     datePatternLength,
1625                           const UChar *timePattern,
1626                           int32_t     timePatternLength,
1627                           UErrorCode  *status);
1628 
1629 /**
1630  * @internal
1631  * @see udat_open
1632  */
1633 typedef UDateFormat* (U_EXPORT2 *UDateFormatOpener) (UDateFormatStyle  timeStyle,
1634                                                     UDateFormatStyle  dateStyle,
1635                                                     const char        *locale,
1636                                                     const UChar       *tzID,
1637                                                     int32_t           tzIDLength,
1638                                                     const UChar       *pattern,
1639                                                     int32_t           patternLength,
1640                                                     UErrorCode        *status);
1641 
1642 /**
1643  * Register a provider factory
1644  * @internal ICU 49
1645  */
1646 U_INTERNAL void U_EXPORT2
1647 udat_registerOpener(UDateFormatOpener opener, UErrorCode *status);
1648 
1649 /**
1650  * Un-Register a provider factory
1651  * @internal ICU 49
1652  */
1653 U_INTERNAL UDateFormatOpener U_EXPORT2
1654 udat_unregisterOpener(UDateFormatOpener opener, UErrorCode *status);
1655 #endif  /* U_HIDE_INTERNAL_API */
1656 
1657 
1658 #endif /* #if !UCONFIG_NO_FORMATTING */
1659 
1660 #endif
1661