| 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 | ||||||||||||||||||||||||||
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Defined in header <cwchar> | ||
constwchar_t* wmemchr(constwchar_t* ptr,wchar_t ch,std::size_t count); | (1) | |
wchar_t* wmemchr( wchar_t* ptr,wchar_t ch,std::size_t count); | (2) | |
Locates the first occurrence of wide characterch in the initialcount wide characters of the wide character array pointed to byptr.
Ifcount is zero, the function returns a null pointer.
Contents |
| ptr | - | pointer to the wide character array to be examined |
| ch | - | wide character to search for |
| count | - | number of wide characters to examine |
Pointer to the location of the wide character, or a null pointer if no such character is found.
#include <clocale>#include <cwchar>#include <iostream>#include <locale> int main(){constwchar_t str[]= L"诺不轻信，故人不负我\0诺不轻许，故我不负人。";wchar_t target= L'许';conststd::size_t sz= sizeof str/ sizeof*str;if(constwchar_t* result= std::wmemchr(str, target, sz)){std::setlocale(LC_ALL,"en_US.utf8");std::wcout.imbue(std::locale("en_US.utf8"));std::wcout<<"Found '"<< target<<"' at position "<< result- str<<'\n';}}
Possible output:
Found '许' at position 14
| searches an array for the first occurrence of a character (function)[edit] | |
| finds the first occurrence of a character (function)[edit] | |
| finds the first occurrence of a wide character in a wide string (function)[edit] | |
(C++11) | finds the first element satisfying specific criteria (function template)[edit] |
C documentation forwmemchr | |
