std::basic_string_view<CharT,Traits>::contains

 

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Strings library

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basic_string

basic_string_view (C++17)

char_traits

 

std::basic_string_view

Member functions basic_string_view::basic_string_view    basic_string_view::operator= Iterators basic_string_view::beginbasic_string_view::cbegin basic_string_view::endbasic_string_view::cend basic_string_view::rbeginbasic_string_view::crbegin basic_string_view::rendbasic_string_view::crend Capacity basic_string_view::sizebasic_string_view::length basic_string_view::max_size basic_string_view::empty Operations basic_string_view::copy basic_string_view::substr basic_string_view::compare basic_string_view::starts_with (C++20) basic_string_view::ends_with (C++20) basic_string_view::contains (C++23) basic_string_view::find basic_string_view::rfind basic_string_view::find_first_of basic_string_view::find_last_of basic_string_view::find_first_not_of basic_string_view::find_last_not_of

Element access basic_string_view::at basic_string_view::operator[] basic_string_view::front basic_string_view::back basic_string_view::data Modifiers basic_string_view::remove_prefix basic_string_view::remove_suffix basic_string_view::swap Constants basic_string_view::npos Non-member functions operator==operator!=operator<operator>operator<=operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20) operator<< operator""sv Helper classes hash<std::string_view>hash<std::wstring_view>hash<std::u8string_view>hash<std::u16string_view>hash<std::u32string_view> (C++20) Deduction guides(C++20)

 

constexprbool contains( basic_string_view sv )constnoexcept;	(1)	(since C++23)
constexprbool contains( CharT c )constnoexcept;	(2)	(since C++23)
constexprbool 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>usingnamespace 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 (C++20)	checks if the string view starts with the given prefix (public member function)
ends_with (C++20)	checks if the string view ends with the given suffix (public member function)
find	find characters in the view (public member function)
substr	returns a substring (public member function)
contains (C++23)	checks if the string contains the given substring or character (public member function of std::basic_string<CharT,Traits,Allocator>)