I am looking for simple practical C++ examples on how to use ICU.
The ICU home page is not helpful in this regar开发者_运维知识库d. I am not interested on what and why Unicode. The few demos are not self contained and not compilable examples ( where are the includes? ) I am looking for something like 'Hello, World' of: How to open and read a file encoded in UTF-8 How to use STL / Boost string functions to manipulate UTF-8 encoded strings etc.There's no special way to read a UTF-8 file unless you need to process a byte order mark (BOM). Because of the way UTF-8 encoding works, functions that read ANSI strings can also read UTF-8 strings.
The following code will read the contents of a file (ANSI or UTF-8) and do a couple of conversions.
#include <fstream>
#include <string>
#include <unicode/unistr.h>
int main(int argc, char** argv) {
std::ifstream f("...");
std::string s;
while (std::getline(f, s)) {
// at this point s contains a line of text
// which may be ANSI or UTF-8 encoded
// convert std::string to ICU's UnicodeString
UnicodeString ucs = UnicodeString::fromUTF8(StringPiece(s.c_str()));
// convert UnicodeString to std::wstring
std::wstring ws;
for (int i = 0; i < ucs.length(); ++i)
ws += static_cast<wchar_t>(ucs[i]);
}
}
Take a look at the online API reference.
If you want to use ICU through Boost, see Boost.Locale.
ICU ≠ Boost, so you will find example of how to use ICU functions to manipulate strings, but not Boost.
Which samples are you looking at? There are samples within the ICU source tree, under icu/source/samples - I think the converter samples there open and close utf-8, also icu/source/extras/uconv which is an 'iconv' like application.
more samples at http://source.icu-project.org/repos/icu/icuapps/trunk/
hope this helps
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