| Localization library | |||||||||||||||||||||||||
| Regular expressions library(C++11) | |||||||||||||||||||||||||
| Formatting library(C++20) | |||||||||||||||||||||||||
| Null-terminated sequence utilities | |||||||||||||||||||||||||
| Byte strings | |||||||||||||||||||||||||
| Multibyte strings | |||||||||||||||||||||||||
| Wide strings | |||||||||||||||||||||||||
| Primitive numeric conversions | |||||||||||||||||||||||||
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| Text encoding identifications | |||||||||||||||||||||||||
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| Functions | ||||||||||||||||||||||||||
| Character classification | ||||||||||||||||||||||||||
| Character manipulation | ||||||||||||||||||||||||||
| Conversions to numeric formats | ||||||||||||||||||||||||||
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| String manipulation | ||||||||||||||||||||||||||
| String examination | ||||||||||||||||||||||||||
| Array manipulation | ||||||||||||||||||||||||||
Defined in header <cwchar> | ||
int wcsncmp(constwchar_t* lhs,constwchar_t* rhs,std::size_t count); | ||
Compares at mostcount wide characters of two null-terminated wide strings. The comparison is done lexicographically.
The sign of the result is the sign of the difference between the values of the first pair of wide characters that differ in the strings being compared.
The behavior is undefined iflhs orrhs are not pointers to null-terminated strings.
Contents |
| lhs, rhs | - | pointers to the null-terminated wide strings to compare |
| count | - | maximum number of characters to compare |
Negative value iflhs appears beforerhs in lexicographical order.
Zero iflhs andrhs compare equal.
Positive value iflhs appears afterrhs in lexicographical order.
#include <clocale>#include <cwchar>#include <iostream>#include <locale> void demo(constwchar_t* lhs,constwchar_t* rhs,int sz){int rc= std::wcsncmp(lhs, rhs, sz);if(rc==0)std::wcout<<"First "<< sz<<" characters of ["<< lhs<<"] equal ["<< rhs<<"]\n";elseif(rc<0)std::wcout<<"First "<< sz<<" characters of ["<< lhs<<"] precede ["<< rhs<<"]\n";elseif(rc>0)std::wcout<<"First "<< sz<<" characters of ["<< lhs<<"] follow ["<< rhs<<"]\n";} int main(){constwchar_t str1[]= L"안녕하세요";constwchar_t str2[]= L"안녕히 가십시오"; std::setlocale(LC_ALL,"en_US.utf8");std::wcout.imbue(std::locale("en_US.utf8")); demo(str1, str2,5); demo(str2, str1,8); demo(str1, str2,2);}
Output:
First 5 characters of [안녕하세요] precede [안녕히 가십시오]First 8 characters of [안녕히 가십시오] follow [안녕하세요]First 2 characters of [안녕하세요] equal [안녕히 가십시오]
| compares a certain number of characters from two strings (function)[edit] | |
| compares two wide strings (function)[edit] | |
| compares a certain amount of wide characters from two arrays (function)[edit] | |
| compares two wide strings in accordance to the current locale (function)[edit] | |
C documentation forwcsncmp | |
