std:: wcslen

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

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

#include <iostream>
#include <cwchar>
int main()
{
    const wchar_t* str = L"Hello, world!";
    std::wcout << "The length of L\"" << str << "\" is " << std::wcslen(str) << '\n';
}

The length of L"Hello, world!" is 13

See also