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constexprbool starts_with(std::basic_string_view<CharT,Traits> 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 begins with the given prefix. The prefix may be one of the following:
sv (which may be a result of implicit conversion from anotherstd::basic_string).All three overloads effectively returnstd::basic_string_view<CharT, Traits>(data(), size()).starts_with(x), wherex is the parameter.
Contents |
| sv | - | a string view which may be a result of implicit conversion from anotherstd::basic_string |
| ch | - | a single character |
| s | - | a null-terminated character string |
true if the string 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>#include <string_view> int main(){usingnamespace std::literals; constauto str="Hello, C++20!"s; assert(""&& str.starts_with("He"sv)// (1)&&!str.starts_with("he"sv)// (1)&& str.starts_with("He"s)// (1) implicit conversion string to string_view&&!str.starts_with("he"s)// (1) implicit conversion string to string_view&& str.starts_with('H')// (2)&&!str.starts_with('h')// (2)&& str.starts_with("He")// (3)&&!str.starts_with("he")// (3));}
(C++20) | checks if the string ends with the given suffix (public member function)[edit] |
(C++20) | checks if the string view starts with the given prefix (public member function of std::basic_string_view<CharT,Traits>)[edit] |
(C++20) | checks if the string view ends with the given suffix (public member function of std::basic_string_view<CharT,Traits>)[edit] |
(C++23) | checks if the string contains the given substring or character (public member function)[edit] |
(C++23) | checks if the string view contains the given substring or character (public member function of std::basic_string_view<CharT,Traits>)[edit] |
| compares two strings (public member function)[edit] | |
| returns a substring (public member function)[edit] |
