std::char_traits<char>::length, std::char_traits<wchar_t>::length, std::char_traits<char8_t>::length, std::char_traits<char16_t>::length, std::char_traits<char32_t>::length
From cppreference.com
< cpp | string | char traits
static std::size_t length( const char_type* s ); |
(constexpr since C++17) | |
Returns the length of the character sequence pointed to by s, that is, the position of the terminating null character (char_type()).
See CharTraits for the general requirements on character traits for X::length
.
Contents |
[edit] Parameters
s | - | pointer to a character sequence to return length of |
[edit] Return value
The length of character sequence pointed to by s.
[edit] Complexity
Linear.
[edit] Example
Run this code
#include <iomanip> #include <iostream> #include <string> void print(const char* str) { std::cout << std::quoted(str) << " has length = " << std::char_traits<char>::length(str) << '\n'; } int main() { print("foo"); std::string s{"booo"}; print(s.c_str()); }
Output:
"foo" has length = 3 "booo" has length = 4