From cppreference.com
constexprboolcontains(std::basic_string_view<CharT,Traits>sv)constnoexcept; (1) (since C++23)constexprboolcontains(CharTch)constnoexcept; (2) (since C++23)constexprboolcontains(constCharT*s)const; (3) (since C++23)Checks if the string contains the given substring. The substring may be one of the following:
1) A string view sv (which may be a result of implicit conversion from another std::basic_string).
2) A single character ch.
3) A null-terminated character string s.
All three overloads are equivalent to returnfind(x)!=npos;, where x is the parameter.
Parameters
sv - a string view which may be a result of implicit conversion from another std::basic_stringch - a single character s - a null-terminated character string Return value
true if the string contains the provided substring, false otherwise.
Notes
macroValueStdFeature
(C++23)contains functions Example
Run this code
#include<iomanip>#include<iostream>#include<string>#include<string_view>#include<type_traits>template<typenameSubstrType>voidtest_substring(conststd::string&str,SubstrTypesubs){constexprchardelim=std::is_scalar_v<SubstrType>?'\'':'\"';std::cout<<std::quoted(str)<<(str.contains(subs)?" contains ":" does not contain ")<<std::quoted(std::string{subs},delim)<<'\n';}intmain(){usingnamespacestd::literals;autohelloWorld="hello world"s;test_substring(helloWorld,"hello"sv);test_substring(helloWorld,"goodbye"sv);test_substring(helloWorld,'w');test_substring(helloWorld,'x');}Output:
"hello world" contains "hello" "hello world" does not contain "goodbye" "hello world" contains 'w' "hello world" does not contain 'x' See also
(C++20)
checks if the string starts with the given prefix
(public member function)
(C++20)
checks if the string ends with the given suffix
(public member function)
finds the first occurrence of the given substring
(public member function)
returns a substring
(public member function)
(C++23)
checks if the string view contains the given substring or character
(public member function of std::basic_string_view<CharT,Traits>)