icuSources/i18n/unicode/udat.h

   1 /*
   2  *******************************************************************************
   3  * Copyright (C) 1996-2009, International Business Machines
   4  * Corporation and others. All Rights Reserved.
   5  *******************************************************************************
   6 */
   7
   8 #ifndef UDAT_H
   9 #define UDAT_H
  10
  11 #include "unicode/utypes.h"
  12
  13 #if !UCONFIG_NO_FORMATTING
  14
  15 #include "unicode/ucal.h"
  16 #include "unicode/unum.h"
  17 /**
  18  * \file
  19  * \brief C API: DateFormat
  20  *
  21  * <h2> Date Format C API</h2>
  22  *
  23  * Date Format C API  consists of functions that convert dates and
  24  * times from their internal representations to textual form and back again in a
  25  * language-independent manner. Converting from the internal representation (milliseconds
  26  * since midnight, January 1, 1970) to text is known as "formatting," and converting
  27  * from text to millis is known as "parsing."  We currently define only one concrete
  28  * structure UDateFormat, which can handle pretty much all normal
  29  * date formatting and parsing actions.
  30  * <P>
  31  * Date Format helps you to format and parse dates for any locale. Your code can
  32  * be completely independent of the locale conventions for months, days of the
  33  * week, or even the calendar format: lunar vs. solar.
  34  * <P>
  35  * To format a date for the current Locale with default time and date style,
  36  * use one of the static factory methods:
  37  * <pre>
  38  * \code
  39  *  UErrorCode status = U_ZERO_ERROR;
  40  *  UChar *myString;
  41  *  int32_t myStrlen = 0;
  42  *  UDateFormat* dfmt = udat_open(UDAT_DEFAULT, UDAT_DEFAULT, NULL, NULL, -1, NULL, -1, &status);
  43  *  myStrlen = udat_format(dfmt, myDate, NULL, myStrlen, NULL, &status);
  44  *  if (status==U_BUFFER_OVERFLOW_ERROR){
  45  *      status=U_ZERO_ERROR;
  46  *      myString=(UChar*)malloc(sizeof(UChar) * (myStrlen+1) );
  47  *      udat_format(dfmt, myDate, myString, myStrlen+1, NULL, &status);
  48  *  }
  49  * \endcode
  50  * </pre>
  51  * If you are formatting multiple numbers, it is more efficient to get the
  52  * format and use it multiple times so that the system doesn't have to fetch the
  53  * information about the local language and country conventions multiple times.
  54  * <pre>
  55  * \code
  56  *  UErrorCode status = U_ZERO_ERROR;
  57  *  int32_t i, myStrlen = 0;
  58  *  UChar* myString;
  59  *  char buffer[1024];
  60  *  UDate myDateArr[] = { 0.0, 100000000.0, 2000000000.0 }; // test values
  61  *  UDateFormat* df = udat_open(UDAT_DEFAULT, UDAT_DEFAULT, NULL, NULL, -1, NULL, 0, &status);
  62  *  for (i = 0; i < 3; i++) {
  63  *      myStrlen = udat_format(df, myDateArr[i], NULL, myStrlen, NULL, &status);
  64  *      if(status == U_BUFFER_OVERFLOW_ERROR){
  65  *          status = U_ZERO_ERROR;
  66  *          myString = (UChar*)malloc(sizeof(UChar) * (myStrlen+1) );
  67  *          udat_format(df, myDateArr[i], myString, myStrlen+1, NULL, &status);
  68  *          printf("%s\n", u_austrcpy(buffer, myString) );
  69  *          free(myString);
  70  *      }
  71  *  }
  72  * \endcode
  73  * </pre>
  74  * To get specific fields of a date, you can use UFieldPosition to
  75  * get specific fields.
  76  * <pre>
  77  * \code
  78  *  UErrorCode status = U_ZERO_ERROR;
  79  *  UFieldPosition pos;
  80  *  UChar *myString;
  81  *  int32_t myStrlen = 0;
  82  *  char buffer[1024];
  83  *
  84  *  pos.field = 1;  // Same as the DateFormat::EField enum
  85  *  UDateFormat* dfmt = udat_open(UDAT_DEFAULT, UDAT_DEFAULT, NULL, -1, NULL, 0, &status);
  86  *  myStrlen = udat_format(dfmt, myDate, NULL, myStrlen, &pos, &status);
  87  *  if (status==U_BUFFER_OVERFLOW_ERROR){
  88  *      status=U_ZERO_ERROR;
  89  *      myString=(UChar*)malloc(sizeof(UChar) * (myStrlen+1) );
  90  *      udat_format(dfmt, myDate, myString, myStrlen+1, &pos, &status);
  91  *  }
  92  *  printf("date format: %s\n", u_austrcpy(buffer, myString));
  93  *  buffer[pos.endIndex] = 0;   // NULL terminate the string.
  94  *  printf("UFieldPosition position equals %s\n", &buffer[pos.beginIndex]);
  95  * \endcode
  96  * </pre>
  97  * To format a date for a different Locale, specify it in the call to
  98  * udat_open()
  99  * <pre>
 100  * \code
 101  *        UDateFormat* df = udat_open(UDAT_SHORT, UDAT_SHORT, "fr_FR", NULL, -1, NULL, 0, &status);
 102  * \endcode
 103  * </pre>
 104  * You can use a DateFormat API udat_parse() to parse.
 105  * <pre>
 106  * \code
 107  *  UErrorCode status = U_ZERO_ERROR;
 108  *  int32_t parsepos=0;
 109  *  UDate myDate = udat_parse(df, myString, u_strlen(myString), &parsepos, &status);
 110  * \endcode
 111  * </pre>
 112  *  You can pass in different options for the arguments for date and time style
 113  *  to control the length of the result; from SHORT to MEDIUM to LONG to FULL.
 114  *  The exact result depends on the locale, but generally:
 115  *  see UDateFormatStyle for more details
 116  * <ul type=round>
 117  *   <li>   UDAT_SHORT is completely numeric, such as 12/13/52 or 3:30pm
 118  *   <li>   UDAT_MEDIUM is longer, such as Jan 12, 1952
 119  *   <li>   UDAT_LONG is longer, such as January 12, 1952 or 3:30:32pm
 120  *   <li>   UDAT_FULL is pretty completely specified, such as
 121  *          Tuesday, April 12, 1952 AD or 3:30:42pm PST.
 122  * </ul>
 123  * You can also set the time zone on the format if you wish.
 124  * <P>
 125  * You can also use forms of the parse and format methods with Parse Position and
 126  * UFieldPosition to allow you to
 127  * <ul type=round>
 128  *   <li>   Progressively parse through pieces of a string.
 129  *   <li>   Align any particular field, or find out where it is for selection
 130  *          on the screen.
 131  * </ul>
 132  */
 133
 134 /** A date formatter.
 135  *  For usage in C programs.
 136  *  @stable ICU 2.6
 137  */
 138 typedef void* UDateFormat;
 139
 140 /** The possible date/time format styles
 141  *  @stable ICU 2.6
 142  */
 143 typedef enum UDateFormatStyle {
 144     /** Full style */
 145     UDAT_FULL,
 146     /** Long style */
 147     UDAT_LONG,
 148     /** Medium style */
 149     UDAT_MEDIUM,
 150     /** Short style */
 151     UDAT_SHORT,
 152     /** Default style */
 153     UDAT_DEFAULT = UDAT_MEDIUM,
 154
 155     /** Bitfield for relative date */
 156     UDAT_RELATIVE = (1 << 7),
 157
 158     UDAT_FULL_RELATIVE = UDAT_FULL | UDAT_RELATIVE,
 159
 160     UDAT_LONG_RELATIVE = UDAT_LONG | UDAT_RELATIVE,
 161
 162     UDAT_MEDIUM_RELATIVE = UDAT_MEDIUM | UDAT_RELATIVE,
 163
 164     UDAT_SHORT_RELATIVE = UDAT_SHORT | UDAT_RELATIVE,
 165
 166
 167     /** No style */
 168     UDAT_NONE = -1,
 169     /** for internal API use only */
 170     UDAT_IGNORE = -2
 171
 172 } UDateFormatStyle;
 173
 174
 175 /**
 176  * @{
 177  * Below are a set of pre-defined skeletons.
 178  *
 179  * <P>
 180  * A skeleton
 181  * <ol>
 182  * <li>
 183  *    only keeps the field pattern letter and ignores all other parts
 184  *    in a pattern, such as space, punctuations, and string literals.
 185  * </li>
 186  * <li>
 187  *    hides the order of fields.
 188  * </li>
 189  * <li>
 190  *    might hide a field's pattern letter length.
 191  *
 192  *    For those non-digit calendar fields, the pattern letter length is
 193  *    important, such as MMM, MMMM, and MMMMM; EEE and EEEE,
 194  *    and the field's pattern letter length is honored.
 195  *
 196  *    For the digit calendar fields,  such as M or MM, d or dd, yy or yyyy,
 197  *    the field pattern length is ignored and the best match, which is defined
 198  *    in date time patterns, will be returned without honor the field pattern
 199  *    letter length in skeleton.
 200  * </li>
 201  * </ol>
 202  *
 203  * @stable ICU 4.0
 204  */
 205
 206 #define UDAT_MINUTE_SECOND              "ms"
 207 #define UDAT_HOUR24_MINUTE              "Hm"
 208 #define UDAT_HOUR24_MINUTE_SECOND       "Hms"
 209 #define UDAT_HOUR_MINUTE_SECOND         "hms"
 210 #define UDAT_STANDALONE_MONTH           "LLLL"
 211 #define UDAT_ABBR_STANDALONE_MONTH      "LLL"
 212 #define UDAT_YEAR_QUARTER               "yQQQ"
 213 #define UDAT_YEAR_ABBR_QUARTER          "yQ"
 214
 215 /** @} */
 216
 217 /**
 218  * @{
 219  * Below are a set of pre-defined skeletons that
 220  * have pre-defined interval patterns in resource files.
 221  * Users are encouraged to use them in date interval format factory methods.
 222  *
 223  */
 224 #define UDAT_HOUR_MINUTE                "hm"
 225 #define UDAT_YEAR                       "y"
 226 #define UDAT_DAY                        "d"
 227 #define UDAT_NUM_MONTH_WEEKDAY_DAY      "MEd"
 228 #define UDAT_YEAR_NUM_MONTH             "yM"
 229 #define UDAT_NUM_MONTH_DAY              "Md"
 230 #define UDAT_YEAR_NUM_MONTH_WEEKDAY_DAY "yMEd"
 231 #define UDAT_ABBR_MONTH_WEEKDAY_DAY     "MMMEd"
 232 #define UDAT_YEAR_MONTH                 "yMMMM"
 233 #define UDAT_YEAR_ABBR_MONTH            "yMMM"
 234 #define UDAT_MONTH_DAY                  "MMMMd"
 235 #define UDAT_ABBR_MONTH_DAY             "MMMd"
 236 #define UDAT_MONTH_WEEKDAY_DAY          "MMMMEEEEd"
 237 #define UDAT_YEAR_ABBR_MONTH_WEEKDAY_DAY "yMMMEd"
 238 #define UDAT_YEAR_MONTH_WEEKDAY_DAY     "yMMMMEEEEd"
 239 #define UDAT_YEAR_MONTH_DAY             "yMMMMd"
 240 #define UDAT_YEAR_ABBR_MONTH_DAY        "yMMMd"
 241 #define UDAT_YEAR_NUM_MONTH_DAY         "yMd"
 242 #define UDAT_NUM_MONTH                  "M"
 243 #define UDAT_ABBR_MONTH                 "MMM"
 244 #define UDAT_MONTH                      "MMMM"
 245 #define UDAT_HOUR_MINUTE_GENERIC_TZ     "hmv"
 246 #define UDAT_HOUR_MINUTE_TZ             "hmz"
 247 #define UDAT_HOUR                       "h"
 248 #define UDAT_HOUR_GENERIC_TZ            "hv"
 249 #define UDAT_HOUR_TZ                    "hz"
 250
 251 /** @} */
 252
 253
 254 /**
 255  * FieldPosition and UFieldPosition selectors for format fields
 256  * defined by DateFormat and UDateFormat.
 257  * @stable ICU 3.0
 258  */
 259 typedef enum UDateFormatField {
 260     /**
 261      * FieldPosition and UFieldPosition selector for 'G' field alignment,
 262      * corresponding to the UCAL_ERA field.
 263      * @stable ICU 3.0
 264      */
 265     UDAT_ERA_FIELD = 0,
 266
 267     /**
 268      * FieldPosition and UFieldPosition selector for 'y' field alignment,
 269      * corresponding to the UCAL_YEAR field.
 270      * @stable ICU 3.0
 271      */
 272     UDAT_YEAR_FIELD = 1,
 273
 274     /**
 275      * FieldPosition and UFieldPosition selector for 'M' field alignment,
 276      * corresponding to the UCAL_MONTH field.
 277      * @stable ICU 3.0
 278      */
 279     UDAT_MONTH_FIELD = 2,
 280
 281     /**
 282      * FieldPosition and UFieldPosition selector for 'd' field alignment,
 283      * corresponding to the UCAL_DATE field.
 284      * @stable ICU 3.0
 285      */
 286     UDAT_DATE_FIELD = 3,
 287
 288     /**
 289      * FieldPosition and UFieldPosition selector for 'k' field alignment,
 290      * corresponding to the UCAL_HOUR_OF_DAY field.
 291      * UDAT_HOUR_OF_DAY1_FIELD is used for the one-based 24-hour clock.
 292      * For example, 23:59 + 01:00 results in 24:59.
 293      * @stable ICU 3.0
 294      */
 295     UDAT_HOUR_OF_DAY1_FIELD = 4,
 296
 297     /**
 298      * FieldPosition and UFieldPosition selector for 'H' field alignment,
 299      * corresponding to the UCAL_HOUR_OF_DAY field.
 300      * UDAT_HOUR_OF_DAY0_FIELD is used for the zero-based 24-hour clock.
 301      * For example, 23:59 + 01:00 results in 00:59.
 302      * @stable ICU 3.0
 303      */
 304     UDAT_HOUR_OF_DAY0_FIELD = 5,
 305
 306     /**
 307      * FieldPosition and UFieldPosition selector for 'm' field alignment,
 308      * corresponding to the UCAL_MINUTE field.
 309      * @stable ICU 3.0
 310      */
 311     UDAT_MINUTE_FIELD = 6,
 312
 313     /**
 314      * FieldPosition and UFieldPosition selector for 's' field alignment,
 315      * corresponding to the UCAL_SECOND field.
 316      * @stable ICU 3.0
 317      */
 318     UDAT_SECOND_FIELD = 7,
 319
 320     /**
 321      * FieldPosition and UFieldPosition selector for 'S' field alignment,
 322      * corresponding to the UCAL_MILLISECOND field.
 323      * @stable ICU 3.0
 324      */
 325     UDAT_FRACTIONAL_SECOND_FIELD = 8,
 326
 327     /**
 328      * FieldPosition and UFieldPosition selector for 'E' field alignment,
 329      * corresponding to the UCAL_DAY_OF_WEEK field.
 330      * @stable ICU 3.0
 331      */
 332     UDAT_DAY_OF_WEEK_FIELD = 9,
 333
 334     /**
 335      * FieldPosition and UFieldPosition selector for 'D' field alignment,
 336      * corresponding to the UCAL_DAY_OF_YEAR field.
 337      * @stable ICU 3.0
 338      */
 339     UDAT_DAY_OF_YEAR_FIELD = 10,
 340
 341     /**
 342      * FieldPosition and UFieldPosition selector for 'F' field alignment,
 343      * corresponding to the UCAL_DAY_OF_WEEK_IN_MONTH field.
 344      * @stable ICU 3.0
 345      */
 346     UDAT_DAY_OF_WEEK_IN_MONTH_FIELD = 11,
 347
 348     /**
 349      * FieldPosition and UFieldPosition selector for 'w' field alignment,
 350      * corresponding to the UCAL_WEEK_OF_YEAR field.
 351      * @stable ICU 3.0
 352      */
 353     UDAT_WEEK_OF_YEAR_FIELD = 12,
 354
 355     /**
 356      * FieldPosition and UFieldPosition selector for 'W' field alignment,
 357      * corresponding to the UCAL_WEEK_OF_MONTH field.
 358      * @stable ICU 3.0
 359      */
 360     UDAT_WEEK_OF_MONTH_FIELD = 13,
 361
 362     /**
 363      * FieldPosition and UFieldPosition selector for 'a' field alignment,
 364      * corresponding to the UCAL_AM_PM field.
 365      * @stable ICU 3.0
 366      */
 367     UDAT_AM_PM_FIELD = 14,
 368
 369     /**
 370      * FieldPosition and UFieldPosition selector for 'h' field alignment,
 371      * corresponding to the UCAL_HOUR field.
 372      * UDAT_HOUR1_FIELD is used for the one-based 12-hour clock.
 373      * For example, 11:30 PM + 1 hour results in 12:30 AM.
 374      * @stable ICU 3.0
 375      */
 376     UDAT_HOUR1_FIELD = 15,
 377
 378     /**
 379      * FieldPosition and UFieldPosition selector for 'K' field alignment,
 380      * corresponding to the UCAL_HOUR field.
 381      * UDAT_HOUR0_FIELD is used for the zero-based 12-hour clock.
 382      * For example, 11:30 PM + 1 hour results in 00:30 AM.
 383      * @stable ICU 3.0
 384      */
 385     UDAT_HOUR0_FIELD = 16,
 386
 387     /**
 388      * FieldPosition and UFieldPosition selector for 'z' field alignment,
 389      * corresponding to the UCAL_ZONE_OFFSET and
 390      * UCAL_DST_OFFSET fields.
 391      * @stable ICU 3.0
 392      */
 393     UDAT_TIMEZONE_FIELD = 17,
 394
 395     /**
 396      * FieldPosition and UFieldPosition selector for 'Y' field alignment,
 397      * corresponding to the UCAL_YEAR_WOY field.
 398      * @stable ICU 3.0
 399      */
 400     UDAT_YEAR_WOY_FIELD = 18,
 401
 402     /**
 403      * FieldPosition and UFieldPosition selector for 'e' field alignment,
 404      * corresponding to the UCAL_DOW_LOCAL field.
 405      * @stable ICU 3.0
 406      */
 407     UDAT_DOW_LOCAL_FIELD = 19,
 408
 409     /**
 410      * FieldPosition and UFieldPosition selector for 'u' field alignment,
 411      * corresponding to the UCAL_EXTENDED_YEAR field.
 412      * @stable ICU 3.0
 413      */
 414     UDAT_EXTENDED_YEAR_FIELD = 20,
 415
 416     /**
 417      * FieldPosition and UFieldPosition selector for 'g' field alignment,
 418      * corresponding to the UCAL_JULIAN_DAY field.
 419      * @stable ICU 3.0
 420      */
 421     UDAT_JULIAN_DAY_FIELD = 21,
 422
 423     /**
 424      * FieldPosition and UFieldPosition selector for 'A' field alignment,
 425      * corresponding to the UCAL_MILLISECONDS_IN_DAY field.
 426      * @stable ICU 3.0
 427      */
 428     UDAT_MILLISECONDS_IN_DAY_FIELD = 22,
 429
 430     /**
 431      * FieldPosition and UFieldPosition selector for 'Z' field alignment,
 432      * corresponding to the UCAL_ZONE_OFFSET and
 433      * UCAL_DST_OFFSET fields.
 434      * @stable ICU 3.0
 435      */
 436     UDAT_TIMEZONE_RFC_FIELD = 23,
 437
 438     /**
 439      * FieldPosition and UFieldPosition selector for 'v' field alignment,
 440      * corresponding to the UCAL_ZONE_OFFSET field.
 441      * @stable ICU 3.4
 442      */
 443     UDAT_TIMEZONE_GENERIC_FIELD = 24,
 444     /**
 445      * FieldPosition selector for 'c' field alignment,
 446      * corresponding to the {@link #UCAL_DATE} field.
 447      * This displays the stand alone day name, if available.
 448      * @stable ICU 3.4
 449      */
 450     UDAT_STANDALONE_DAY_FIELD = 25,
 451
 452     /**
 453      * FieldPosition selector for 'L' field alignment,
 454      * corresponding to the {@link #UCAL_MONTH} field.
 455      * This displays the stand alone month name, if available.
 456      * @stable ICU 3.4
 457      */
 458     UDAT_STANDALONE_MONTH_FIELD = 26,
 459
 460     /**
 461      * FieldPosition selector for "Q" field alignment,
 462      * corresponding to quarters. This is implemented
 463      * using the {@link #UCAL_MONTH} field. This
 464      * displays the quarter.
 465      * @stable ICU 3.6
 466      */
 467     UDAT_QUARTER_FIELD = 27,
 468
 469     /**
 470      * FieldPosition selector for the "q" field alignment,
 471      * corresponding to stand-alone quarters. This is
 472      * implemented using the {@link #UCAL_MONTH} field.
 473      * This displays the stand-alone quarter.
 474      * @stable ICU 3.6
 475      */
 476     UDAT_STANDALONE_QUARTER_FIELD = 28,
 477
 478     /**
 479      * FieldPosition and UFieldPosition selector for 'V' field alignment,
 480      * corresponding to the UCAL_ZONE_OFFSET field.
 481      * @stable ICU 3.8
 482      */
 483     UDAT_TIMEZONE_SPECIAL_FIELD = 29,
 484
 485    /**
 486      * Number of FieldPosition and UFieldPosition selectors for
 487      * DateFormat and UDateFormat.
 488      * Valid selectors range from 0 to UDAT_FIELD_COUNT-1.
 489      * This value is subject to change if new fields are defined
 490      * in the future.
 491      * @stable ICU 3.0
 492      */
 493     UDAT_FIELD_COUNT = 30
 494
 495 } UDateFormatField;
 496
 497 /**
 498  * Open a new UDateFormat for formatting and parsing dates and times.
 499  * A UDateFormat may be used to format dates in calls to {@link #udat_format },
 500  * and to parse dates in calls to {@link #udat_parse }.
 501  * @param timeStyle The style used to format times; one of UDAT_FULL, UDAT_LONG,
 502  * UDAT_MEDIUM, UDAT_SHORT, UDAT_DEFAULT, or UDAT_NONE (relative time styles
 503  * are not currently supported)
 504  * @param dateStyle The style used to format dates; one of UDAT_FULL, UDAT_LONG,
 505  * UDAT_MEDIUM, UDAT_SHORT, UDAT_DEFAULT, UDAT_FULL_RELATIVE, UDAT_LONG_RELATIVE,
 506  * UDAT_MEDIUM_RELATIVE, UDAT_SHORT_RELATIVE, or UDAT_NONE
 507  * @param locale The locale specifying the formatting conventions
 508  * @param tzID A timezone ID specifying the timezone to use.  If 0, use
 509  * the default timezone.
 510  * @param tzIDLength The length of tzID, or -1 if null-terminated.
 511  * @param pattern A pattern specifying the format to use.
 512  * @param patternLength The number of characters in the pattern, or -1 if null-terminated.
 513  * @param status A pointer to an UErrorCode to receive any errors
 514  * @return A pointer to a UDateFormat to use for formatting dates and times, or 0 if
 515  * an error occurred.
 516  * @stable ICU 2.0
 517  */
 518 U_STABLE UDateFormat* U_EXPORT2
 519 udat_open(UDateFormatStyle  timeStyle,
 520           UDateFormatStyle  dateStyle,
 521           const char        *locale,
 522           const UChar       *tzID,
 523           int32_t           tzIDLength,
 524           const UChar       *pattern,
 525           int32_t           patternLength,
 526           UErrorCode        *status);
 527
 528
 529 /**
 530 * Close a UDateFormat.
 531 * Once closed, a UDateFormat may no longer be used.
 532 * @param format The formatter to close.
 533 * @stable ICU 2.0
 534 */
 535 U_STABLE void U_EXPORT2
 536 udat_close(UDateFormat* format);
 537
 538 /**
 539  * Open a copy of a UDateFormat.
 540  * This function performs a deep copy.
 541  * @param fmt The format to copy
 542  * @param status A pointer to an UErrorCode to receive any errors.
 543  * @return A pointer to a UDateFormat identical to fmt.
 544  * @stable ICU 2.0
 545  */
 546 U_STABLE UDateFormat* U_EXPORT2
 547 udat_clone(const UDateFormat *fmt,
 548        UErrorCode *status);
 549
 550 /**
 551 * Format a date using an UDateFormat.
 552 * The date will be formatted using the conventions specified in {@link #udat_open }
 553 * @param format The formatter to use
 554 * @param dateToFormat The date to format
 555 * @param result A pointer to a buffer to receive the formatted number.
 556 * @param resultLength The maximum size of result.
 557 * @param position A pointer to a UFieldPosition.  On input, position->field
 558 * is read.  On output, position->beginIndex and position->endIndex indicate
 559 * the beginning and ending indices of field number position->field, if such
 560 * a field exists.  This parameter may be NULL, in which case no field
 561 * position data is returned.
 562 * @param status A pointer to an UErrorCode to receive any errors
 563 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
 564 * @see udat_parse
 565 * @see UFieldPosition
 566 * @stable ICU 2.0
 567 */
 568 U_STABLE int32_t U_EXPORT2
 569 udat_format(    const    UDateFormat*    format,
 570                         UDate           dateToFormat,
 571                         UChar*          result,
 572                         int32_t         resultLength,
 573                         UFieldPosition* position,
 574                         UErrorCode*     status);
 575
 576 /**
 577 * Parse a string into an date/time using a UDateFormat.
 578 * The date will be parsed using the conventions specified in {@link #udat_open }
 579 * @param format The formatter to use.
 580 * @param text The text to parse.
 581 * @param textLength The length of text, or -1 if null-terminated.
 582 * @param parsePos If not 0, on input a pointer to an integer specifying the offset at which
 583 * to begin parsing.  If not 0, on output the offset at which parsing ended.
 584 * @param status A pointer to an UErrorCode to receive any errors
 585 * @return The value of the parsed date/time
 586 * @see udat_format
 587 * @stable ICU 2.0
 588 */
 589 U_STABLE UDate U_EXPORT2
 590 udat_parse(    const    UDateFormat*    format,
 591             const    UChar*          text,
 592                     int32_t         textLength,
 593                     int32_t         *parsePos,
 594                     UErrorCode      *status);
 595
 596 /**
 597 * Parse a string into an date/time using a UDateFormat.
 598 * The date will be parsed using the conventions specified in {@link #udat_open }
 599 * @param format The formatter to use.
 600 * @param calendar The calendar in which to store the parsed data.
 601 * @param text The text to parse.
 602 * @param textLength The length of text, or -1 if null-terminated.
 603 * @param parsePos If not 0, on input a pointer to an integer specifying the offset at which
 604 * to begin parsing.  If not 0, on output the offset at which parsing ended.
 605 * @param status A pointer to an UErrorCode to receive any errors
 606 * @see udat_format
 607 * @stable ICU 2.0
 608 */
 609 U_STABLE void U_EXPORT2
 610 udat_parseCalendar(const    UDateFormat*    format,
 611                             UCalendar*      calendar,
 612                    const    UChar*          text,
 613                             int32_t         textLength,
 614                             int32_t         *parsePos,
 615                             UErrorCode      *status);
 616
 617 /**
 618 * Determine if an UDateFormat will perform lenient parsing.
 619 * With lenient parsing, the parser may use heuristics to interpret inputs that do not
 620 * precisely match the pattern. With strict parsing, inputs must match the pattern.
 621 * @param fmt The formatter to query
 622 * @return TRUE if fmt is set to perform lenient parsing, FALSE otherwise.
 623 * @see udat_setLenient
 624 * @stable ICU 2.0
 625 */
 626 U_STABLE UBool U_EXPORT2
 627 udat_isLenient(const UDateFormat* fmt);
 628
 629 /**
 630 * Specify whether an UDateFormat will perform lenient parsing.
 631 * With lenient parsing, the parser may use heuristics to interpret inputs that do not
 632 * precisely match the pattern. With strict parsing, inputs must match the pattern.
 633 * @param fmt The formatter to set
 634 * @param isLenient TRUE if fmt should perform lenient parsing, FALSE otherwise.
 635 * @see dat_isLenient
 636 * @stable ICU 2.0
 637 */
 638 U_STABLE void U_EXPORT2
 639 udat_setLenient(    UDateFormat*    fmt,
 640                     UBool          isLenient);
 641
 642 /**
 643 * Get the UCalendar associated with an UDateFormat.
 644 * A UDateFormat uses a UCalendar to convert a raw value to, for example,
 645 * the day of the week.
 646 * @param fmt The formatter to query.
 647 * @return A pointer to the UCalendar used by fmt.
 648 * @see udat_setCalendar
 649 * @stable ICU 2.0
 650 */
 651 U_STABLE const UCalendar* U_EXPORT2
 652 udat_getCalendar(const UDateFormat* fmt);
 653
 654 /**
 655 * Set the UCalendar associated with an UDateFormat.
 656 * A UDateFormat uses a UCalendar to convert a raw value to, for example,
 657 * the day of the week.
 658 * @param fmt The formatter to set.
 659 * @param calendarToSet A pointer to an UCalendar to be used by fmt.
 660 * @see udat_setCalendar
 661 * @stable ICU 2.0
 662 */
 663 U_STABLE void U_EXPORT2
 664 udat_setCalendar(            UDateFormat*    fmt,
 665                     const   UCalendar*      calendarToSet);
 666
 667 /**
 668 * Get the UNumberFormat associated with an UDateFormat.
 669 * A UDateFormat uses a UNumberFormat to format numbers within a date,
 670 * for example the day number.
 671 * @param fmt The formatter to query.
 672 * @return A pointer to the UNumberFormat used by fmt to format numbers.
 673 * @see udat_setNumberFormat
 674 * @stable ICU 2.0
 675 */
 676 U_STABLE const UNumberFormat* U_EXPORT2
 677 udat_getNumberFormat(const UDateFormat* fmt);
 678
 679 /**
 680 * Set the UNumberFormat associated with an UDateFormat.
 681 * A UDateFormat uses a UNumberFormat to format numbers within a date,
 682 * for example the day number.
 683 * @param fmt The formatter to set.
 684 * @param numberFormatToSet A pointer to the UNumberFormat to be used by fmt to format numbers.
 685 * @see udat_getNumberFormat
 686 * @stable ICU 2.0
 687 */
 688 U_STABLE void U_EXPORT2
 689 udat_setNumberFormat(            UDateFormat*    fmt,
 690                         const   UNumberFormat*  numberFormatToSet);
 691
 692 /**
 693 * Get a locale for which date/time formatting patterns are available.
 694 * A UDateFormat in a locale returned by this function will perform the correct
 695 * formatting and parsing for the locale.
 696 * @param localeIndex The index of the desired locale.
 697 * @return A locale for which date/time formatting patterns are available, or 0 if none.
 698 * @see udat_countAvailable
 699 * @stable ICU 2.0
 700 */
 701 U_STABLE const char* U_EXPORT2
 702 udat_getAvailable(int32_t localeIndex);
 703
 704 /**
 705 * Determine how many locales have date/time  formatting patterns available.
 706 * This function is most useful as determining the loop ending condition for
 707 * calls to {@link #udat_getAvailable }.
 708 * @return The number of locales for which date/time formatting patterns are available.
 709 * @see udat_getAvailable
 710 * @stable ICU 2.0
 711 */
 712 U_STABLE int32_t U_EXPORT2
 713 udat_countAvailable(void);
 714
 715 /**
 716 * Get the year relative to which all 2-digit years are interpreted.
 717 * For example, if the 2-digit start year is 2100, the year 99 will be
 718 * interpreted as 2199.
 719 * @param fmt The formatter to query.
 720 * @param status A pointer to an UErrorCode to receive any errors
 721 * @return The year relative to which all 2-digit years are interpreted.
 722 * @see udat_Set2DigitYearStart
 723 * @stable ICU 2.0
 724 */
 725 U_STABLE UDate U_EXPORT2
 726 udat_get2DigitYearStart(    const   UDateFormat     *fmt,
 727                                     UErrorCode      *status);
 728
 729 /**
 730 * Set the year relative to which all 2-digit years will be interpreted.
 731 * For example, if the 2-digit start year is 2100, the year 99 will be
 732 * interpreted as 2199.
 733 * @param fmt The formatter to set.
 734 * @param d The year relative to which all 2-digit years will be interpreted.
 735 * @param status A pointer to an UErrorCode to receive any errors
 736 * @see udat_Set2DigitYearStart
 737 * @stable ICU 2.0
 738 */
 739 U_STABLE void U_EXPORT2
 740 udat_set2DigitYearStart(    UDateFormat     *fmt,
 741                             UDate           d,
 742                             UErrorCode      *status);
 743
 744 /**
 745 * Extract the pattern from a UDateFormat.
 746 * The pattern will follow the pattern syntax rules.
 747 * @param fmt The formatter to query.
 748 * @param localized TRUE if the pattern should be localized, FALSE otherwise.
 749 * @param result A pointer to a buffer to receive the pattern.
 750 * @param resultLength The maximum size of result.
 751 * @param status A pointer to an UErrorCode to receive any errors
 752 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
 753 * @see udat_applyPattern
 754 * @stable ICU 2.0
 755 */
 756 U_STABLE int32_t U_EXPORT2
 757 udat_toPattern(    const   UDateFormat     *fmt,
 758                         UBool          localized,
 759                         UChar           *result,
 760                         int32_t         resultLength,
 761                         UErrorCode      *status);
 762
 763 /**
 764 * Set the pattern used by an UDateFormat.
 765 * The pattern should follow the pattern syntax rules.
 766 * @param format The formatter to set.
 767 * @param localized TRUE if the pattern is localized, FALSE otherwise.
 768 * @param pattern The new pattern
 769 * @param patternLength The length of pattern, or -1 if null-terminated.
 770 * @see udat_toPattern
 771 * @stable ICU 2.0
 772 */
 773 U_STABLE void U_EXPORT2
 774 udat_applyPattern(            UDateFormat     *format,
 775                             UBool          localized,
 776                     const   UChar           *pattern,
 777                             int32_t         patternLength);
 778
 779 /**
 780  * The possible types of date format symbols
 781  * @stable ICU 2.6
 782  */
 783 typedef enum UDateFormatSymbolType {
 784     /** The era names, for example AD */
 785     UDAT_ERAS,
 786     /** The month names, for example February */
 787     UDAT_MONTHS,
 788     /** The short month names, for example Feb. */
 789     UDAT_SHORT_MONTHS,
 790     /** The weekday names, for example Monday */
 791     UDAT_WEEKDAYS,
 792     /** The short weekday names, for example Mon. */
 793     UDAT_SHORT_WEEKDAYS,
 794     /** The AM/PM names, for example AM */
 795     UDAT_AM_PMS,
 796     /** The localized characters */
 797     UDAT_LOCALIZED_CHARS,
 798     /** The long era names, for example Anno Domini */
 799     UDAT_ERA_NAMES,
 800     /** The narrow month names, for example F */
 801     UDAT_NARROW_MONTHS,
 802     /** The narrow weekday names, for example N */
 803     UDAT_NARROW_WEEKDAYS,
 804     /** Standalone context versions of months */
 805     UDAT_STANDALONE_MONTHS,
 806     UDAT_STANDALONE_SHORT_MONTHS,
 807     UDAT_STANDALONE_NARROW_MONTHS,
 808     /** Standalone context versions of weekdays */
 809     UDAT_STANDALONE_WEEKDAYS,
 810     UDAT_STANDALONE_SHORT_WEEKDAYS,
 811     UDAT_STANDALONE_NARROW_WEEKDAYS,
 812     /** The quarters, for example 1st Quarter */
 813     UDAT_QUARTERS,
 814     /** The short quarter names, for example Q1 */
 815     UDAT_SHORT_QUARTERS,
 816     /** Standalone context versions of quarters */
 817     UDAT_STANDALONE_QUARTERS,
 818     UDAT_STANDALONE_SHORT_QUARTERS
 819
 820 } UDateFormatSymbolType;
 821
 822 struct UDateFormatSymbols;
 823 /** Date format symbols.
 824  *  For usage in C programs.
 825  *  @stable ICU 2.6
 826  */
 827 typedef struct UDateFormatSymbols UDateFormatSymbols;
 828
 829 /**
 830 * Get the symbols associated with an UDateFormat.
 831 * The symbols are what a UDateFormat uses to represent locale-specific data,
 832 * for example month or day names.
 833 * @param fmt The formatter to query.
 834 * @param type The type of symbols to get.  One of UDAT_ERAS, UDAT_MONTHS, UDAT_SHORT_MONTHS,
 835 * UDAT_WEEKDAYS, UDAT_SHORT_WEEKDAYS, UDAT_AM_PMS, or UDAT_LOCALIZED_CHARS
 836 * @param symbolIndex The desired symbol of type type.
 837 * @param result A pointer to a buffer to receive the pattern.
 838 * @param resultLength The maximum size of result.
 839 * @param status A pointer to an UErrorCode to receive any errors
 840 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
 841 * @see udat_countSymbols
 842 * @see udat_setSymbols
 843 * @stable ICU 2.0
 844 */
 845 U_STABLE int32_t U_EXPORT2
 846 udat_getSymbols(const   UDateFormat             *fmt,
 847                         UDateFormatSymbolType   type,
 848                         int32_t                 symbolIndex,
 849                         UChar                   *result,
 850                         int32_t                 resultLength,
 851                         UErrorCode              *status);
 852
 853 /**
 854 * Count the number of particular symbols for an UDateFormat.
 855 * This function is most useful as for detemining the loop termination condition
 856 * for calls to {@link #udat_getSymbols }.
 857 * @param fmt The formatter to query.
 858 * @param type The type of symbols to count.  One of UDAT_ERAS, UDAT_MONTHS, UDAT_SHORT_MONTHS,
 859 * UDAT_WEEKDAYS, UDAT_SHORT_WEEKDAYS, UDAT_AM_PMS, or UDAT_LOCALIZED_CHARS
 860 * @return The number of symbols of type type.
 861 * @see udat_getSymbols
 862 * @see udat_setSymbols
 863 * @stable ICU 2.0
 864 */
 865 U_STABLE int32_t U_EXPORT2
 866 udat_countSymbols(    const    UDateFormat                *fmt,
 867                             UDateFormatSymbolType    type);
 868
 869 /**
 870 * Set the symbols associated with an UDateFormat.
 871 * The symbols are what a UDateFormat uses to represent locale-specific data,
 872 * for example month or day names.
 873 * @param format The formatter to set
 874 * @param type The type of symbols to set.  One of UDAT_ERAS, UDAT_MONTHS, UDAT_SHORT_MONTHS,
 875 * UDAT_WEEKDAYS, UDAT_SHORT_WEEKDAYS, UDAT_AM_PMS, or UDAT_LOCALIZED_CHARS
 876 * @param symbolIndex The index of the symbol to set of type type.
 877 * @param value The new value
 878 * @param valueLength The length of value, or -1 if null-terminated
 879 * @param status A pointer to an UErrorCode to receive any errors
 880 * @see udat_getSymbols
 881 * @see udat_countSymbols
 882 * @stable ICU 2.0
 883 */
 884 U_STABLE void U_EXPORT2
 885 udat_setSymbols(    UDateFormat             *format,
 886                     UDateFormatSymbolType   type,
 887                     int32_t                 symbolIndex,
 888                     UChar                   *value,
 889                     int32_t                 valueLength,
 890                     UErrorCode              *status);
 891
 892 /**
 893  * Get the locale for this date format object.
 894  * You can choose between valid and actual locale.
 895  * @param fmt The formatter to get the locale from
 896  * @param type type of the locale we're looking for (valid or actual)
 897  * @param status error code for the operation
 898  * @return the locale name
 899  * @stable ICU 2.8
 900  */
 901 U_STABLE const char* U_EXPORT2
 902 udat_getLocaleByType(const UDateFormat *fmt,
 903                      ULocDataLocaleType type,
 904                      UErrorCode* status);
 905
 906 /**
 907 * Extract the date pattern from a UDateFormat set for relative date formatting.
 908 * The pattern will follow the pattern syntax rules.
 909 * @param fmt The formatter to query.
 910 * @param result A pointer to a buffer to receive the pattern.
 911 * @param resultLength The maximum size of result.
 912 * @param status A pointer to a UErrorCode to receive any errors
 913 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
 914 * @see udat_applyPatternRelative
 915 * @internal ICU 4.2 technology preview
 916 */
 917 U_INTERNAL int32_t U_EXPORT2
 918 udat_toPatternRelativeDate(const UDateFormat *fmt,
 919                            UChar             *result,
 920                            int32_t           resultLength,
 921                            UErrorCode        *status);
 922
 923 /**
 924 * Extract the time pattern from a UDateFormat set for relative date formatting.
 925 * The pattern will follow the pattern syntax rules.
 926 * @param fmt The formatter to query.
 927 * @param result A pointer to a buffer to receive the pattern.
 928 * @param resultLength The maximum size of result.
 929 * @param status A pointer to a UErrorCode to receive any errors
 930 * @return The total buffer size needed; if greater than resultLength, the output was truncated.
 931 * @see udat_applyPatternRelative
 932 * @internal ICU 4.2 technology preview
 933 */
 934 U_INTERNAL int32_t U_EXPORT2
 935 udat_toPatternRelativeTime(const UDateFormat *fmt,
 936                            UChar             *result,
 937                            int32_t           resultLength,
 938                            UErrorCode        *status);
 939
 940 /**
 941 * Set the date & time patterns used by a UDateFormat set for relative date formatting.
 942 * The patterns should follow the pattern syntax rules.
 943 * @param format The formatter to set.
 944 * @param datePattern The new date pattern
 945 * @param datePatternLength The length of datePattern, or -1 if null-terminated.
 946 * @param timePattern The new time pattern
 947 * @param timePatternLength The length of timePattern, or -1 if null-terminated.
 948 * @param status A pointer to a UErrorCode to receive any errors
 949 * @see udat_toPatternRelativeDate, udat_toPatternRelativeTime
 950 * @internal ICU 4.2 technology preview
 951 */
 952 U_INTERNAL void U_EXPORT2
 953 udat_applyPatternRelative(UDateFormat *format,
 954                           const UChar *datePattern,
 955                           int32_t     datePatternLength,
 956                           const UChar *timePattern,
 957                           int32_t     timePatternLength,
 958                           UErrorCode  *status);
 959
 960 #endif /* #if !UCONFIG_NO_FORMATTING */
 961
 962 #endif