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constexprbool starts_with( basic_string_view sv)constnoexcept; | (1) | (since C++20) |
constexprbool starts_with( CharT ch)constnoexcept; | (2) | (since C++20) |
constexprbool starts_with(const CharT* s)const; | (3) | (since C++20) |
Checks if the string view begins with the given prefix, where
Contents |
| sv | - | a string view which may be a result of implicit conversion fromstd::basic_string |
| ch | - | a single character |
| s | - | a null-terminated character string |
true if the string view begins with the provided prefix,false otherwise.
| Feature-test macro | Value | Std | Feature |
|---|---|---|---|
__cpp_lib_starts_ends_with | 201711L | (C++20) | String prefix and suffix checking:starts_with() andends_with() |
#include <cassert>#include <string_view> int main(){usingnamespace std::literals; assert(""// (1) starts_with( basic_string_view )&&"https://cppreference.com"sv.starts_with("http"sv)==true&&"https://cppreference.com"sv.starts_with("ftp"sv)==false // (2) starts_with( CharT )&&"C++20"sv.starts_with('C')==true&&"C++20"sv.starts_with('J')==false // (3) starts_with( const CharT* )&&std::string_view("string_view").starts_with("string")==true&&std::string_view("string_view").starts_with("String")==false);}
(C++20) | checks if the string view ends with the given suffix (public member function)[edit] |
(C++20) | checks if the string starts with the given prefix (public member function of std::basic_string<CharT,Traits,Allocator>)[edit] |
(C++20) | checks if the string ends with the given suffix (public member function of std::basic_string<CharT,Traits,Allocator>)[edit] |
(C++23) | checks if the string contains the given substring or character (public member function of std::basic_string<CharT,Traits,Allocator>)[edit] |
(C++23) | checks if the string view contains the given substring or character (public member function)[edit] |
| compares two views (public member function)[edit] |
