Use Class Hierarchy or Alphabetical List or Compound List to find the class you are interested in. For example, to find BreakIterator, you can go to the Alphabetical List, then click on "BreakIterator". Once you are at the class, you will find an inheritance chart, a list of the public members, a detailed description of the class, then detailed member descriptions.
Use Module List or File Members to find a list of all the functions and constants. For example, to find BreakIterator functions you would click on File List, then find "ubrk.h" and click on it. You will find descriptions of Defines, Typedefs, Enumerations, and Functions, with detailed descriptions below. If you want to find a specific function, such as ubrk_next(), then click first on File Members, then use your browser Find dialog to search for "ubrk_next()".
The API References for each release of ICU are also available as a zip file from the ICU download page.
| Module Name | C | C++ |
| Basic Types and Constants | utypes.h | utypes.h |
| Strings and Character Iteration | ustring.h, utf.h | UnicodeString, CharacterIterator |
| Unicode Character Properties and Names | uchar.h | uchar.h C API |
| Codepage Conversion | ucnv.h | ucnv.h C API |
| Unicode Text Compression | ucnv.h (encoding name "SCSU" or "BOCU-1") | ucnv.h C API |
| Locales | uloc.h | Locale |
| Resource Bundles | ures.h | ResourceBundle |
| Normalization | unorm.h | Normalizer |
| Calendars | ucal.h | Calendar |
| Date and Time Formatting | udat.h | DateFormat |
| Message Formatting | umsg.h | MessageFormat |
| Number Formatting | unum.h | NumberFormat |
| Number Spellout (Rule Based Number Formatting) | unum.h (use UNUM_SPELLOUT) | RuleBasedNumberFormat |
| Text Transformation (Transliteration) | utrans.h | Transliterator |
| Bidirectional Algorithm | ubidi.h | ubidi.h C API |
| Arabic Shaping | ushape.h | ushape.h C API |
| Collation | ucol.h | Collator |
| String Searching | usearch.h | StringSearch |
| Text Boundary Analysis (Break Iteration) | ubrk.h | BreakIterator |
| Unicode Set | uset.h | UnicodeSet |
| Regular Expressions | uregex.h | RegexPattern, RegexMatcher |
| StringPrep | usprep.h | usprep.h C API |
| International Domain Names in Applications | uidna.h | uidna.h C API |
| Universal Time Scale | utmscale.h | utmscale.h C API |
| Basic Layout Engine Types and Constants | (no C API) | LETypes.h |
| Complex Text Layout | (no C API) | LayoutEngine, ParagraphLayout |
| ICU I/O | ustdio.h | ustream.h |
1.5.6