NAME¶

std::basic_string_view::contains - std::basic_string_view::contains

Synopsis¶

constexpr bool contains( basic_string_view sv ) const noexcept; (1) (since C++23)
constexpr bool contains( CharT c ) const noexcept; (2) (since C++23)
constexpr bool contains( const CharT* s ) const; (3) (since C++23)

Checks if the string view contains the given substring, where

1) the substring is a string view.
2) the substring is a single character.
3) the substring is a null-terminated character string.

All three overloads are equivalent to return find(x) != npos;, where x is the
parameter.

Parameters¶

sv - a string view
c - a single character
s - a null-terminated character string

Return value¶

true if the string view contains the provided substring, false otherwise.

Notes¶

Feature-test macro Value Std Feature
__cpp_lib_string_contains 202011L (C++23) contains functions

Example¶

// Run this code

#include <string_view>
using namespace std::literals;

static_assert
(
// bool contains(basic_string_view x) const noexcept;
"https://cppreference.com"sv.contains("cpp"sv) == true and
"https://cppreference.com"sv.contains("php"sv) == false and

// bool contains(CharT x) const noexcept;
"C++23"sv.contains('+') == true and
"C++23"sv.contains('-') == false and

// bool contains(const CharT* x) const;
std::string_view("basic_string_view").contains("string") == true and
std::string_view("basic_string_view").contains("String") == false
);

int main() {}

See also¶

starts_with checks if the string view starts with the given prefix
(C++20) (public member function)
ends_with checks if the string view ends with the given suffix
(C++20) (public member function)
find find characters in the view
(public member function)
substr returns a substring
(public member function)
contains checks if the string contains the given substring or character
(C++23) (public member function of std::basic_string<CharT,Traits,Allocator>)