NAME¶

std::wcslen - std::wcslen

Synopsis¶

Defined in header <cwchar>
std::size_t wcslen( const wchar_t* str );

Returns the length of a wide string, that is the number of non-null wide characters
that precede the terminating null wide character.

The behavior is undefined if there is no null character in the wide character array
pointed to by str.

Parameters¶

str - pointer to the null-terminated wide string to be examined

Return value¶

The length of the null-terminated wide string str.

Possible implementation¶

std::size_t wcslen(const wchar_t* start)
{
// NB: start is not checked for nullptr!
const wchar_t* end = start;
while (*end != L'\0')
++end;
return end - start;
}

Example¶

// Run this code

#include <clocale>
#include <cwchar>
#include <iostream>

int main()
{
const wchar_t* str = L"爆ぜろリアル！弾けろシナプス！パニッシュメントディス、ワールド！";

std::setlocale(LC_ALL, "en_US.utf8");
std::wcout.imbue(std::locale("en_US.utf8"));
std::wcout << "The length of \"" << str << "\" is " << std::wcslen(str) << '\n';
}

Output:¶

The length of "爆ぜろリアル！弾けろシナプス！パニッシュメントディス、ワールド！" is 32

See also¶

strlen returns the length of a given string
(function)
mblen returns the number of bytes in the next multibyte character
(function)
C documentation for
wcslen