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- C++11
- C++14
- C++17
- C++20
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- C++ è¯è¨
- C++ å ³é®è¯
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- C++ æ ååºå¤´æä»¶
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- åè½ç¹æ§æµè¯ (C++20)
- å·¥å ·åº
- ç±»åæ¯æï¼åºæ¬ç±»åãRTTIãç±»åç¹æ§ï¼
- æ¦å¿µåº (C++20)
- é误å¤ç
- 卿å å管ç
- æ¥æåæ¶é´å·¥å ·
- å符串åº
- std::basic_string
- std::basic_string<CharT,Traits,Allocator>::npos
- std::basic_string<CharT,Traits,Allocator>::at
- std::hash (std::string, std::wstring, std::u16string, std::u32string, std::pmr::string, std::pmr::wstring, std::pmr::u16string, std::pmr::u32string)
- std::basic_string<CharT,Traits,Allocator>::assign
- std::basic_string<CharT,Traits,Allocator>::get_allocator
- std::basic_string<CharT,Traits,Allocator>::substr
- std::basic_string<CharT,Traits,Allocator>::basic_string
- std::basic_string<CharT,Traits,Allocator>::operator=
- std::basic_string<CharT,Traits,Allocator>::operator[]
- std::basic_string<CharT,Traits,Allocator>::front
- std::basic_string<CharT,Traits,Allocator>::back
- std::basic_string<CharT,Traits,Allocator>::data
- std::basic_string<CharT,Traits,Allocator>::c_str
- std::basic_string<CharT,Traits,Allocator>::operator basic_string_view
- std::basic_string<CharT,Traits,Allocator>::begin, std::basic_string<CharT,Traits,Allocator>::cbegin
- std::basic_string<CharT,Traits,Allocator>::end, std::basic_string<CharT,Traits,Allocator>::cend
- std::basic_string<CharT,Traits,Allocator>::rbegin, std::basic_string<CharT,Traits,Allocator>::crbegin
- std::basic_string<CharT,Traits,Allocator>::rend, std::basic_string<CharT,Traits,Allocator>::crend
- std::basic_string<CharT,Traits,Allocator>::empty
- std::basic_string<CharT,Traits,Allocator>::size, std::basic_string<CharT,Traits,Allocator>::length
- std::basic_string<CharT,Traits,Allocator>::max_size
- std::basic_string<CharT,Traits,Allocator>::reserve
- std::basic_string<CharT,Traits,Allocator>::capacity
- std::basic_string<CharT,Traits,Allocator>::shrink_to_fit
- std::basic_string<CharT,Traits,Allocator>::clear
- std::basic_string<CharT,Traits,Allocator>::insert
- std::basic_string<CharT,Traits,Allocator>::erase
- std::basic_string<CharT,Traits,Allocator>::push_back
- std::basic_string<CharT,Traits,Allocator>::pop_back
- std::basic_string<CharT,Traits,Allocator>::append
- std::basic_string<CharT,Traits,Allocator>::operator+=
- std::basic_string<CharT,Traits,Allocator>::compare
- std::basic_string<CharT,Traits,Allocator>::starts_with
- std::basic_string<CharT,Traits,Allocator>::ends_with
- std::basic_string<CharT,Traits,Allocator>::replace
- std::basic_string<CharT,Traits,Allocator>::copy
- std::basic_string<CharT,Traits,Allocator>::resize
- std::basic_string<CharT,Traits,Allocator>::swap
- std::basic_string<CharT,Traits,Allocator>::find
- std::basic_string<CharT,Traits,Allocator>::rfind
- std::basic_string<CharT,Traits,Allocator>::find_first_of
- std::basic_string<CharT,Traits,Allocator>::find_first_not_of
- std::basic_string<CharT,Traits,Allocator>::find_last_of
- std::basic_string<CharT,Traits,Allocator>::find_last_not_of
- std::operator+(std::basic_string)
- std::swap(std::basic_string)
- std::literals::string_literals::operator""s
- std::erase, std::erase_if (std::basic_string)
- operator<<,>>(std::basic_string)
- std::getline
- operator==,!=,<,<=,>,>=,<=>(std::basic_string)
- std::stoi, std::stol, std::stoll
- std::stoul, std::stoull
- std::stof, std::stod, std::stold
- std::to_string
- std::to_wstring
- std::basic_string çæ¨å¯¼æå¼
- std::basic_string_view
- ç©ºç»æ¢åèå符串
- ç©ºç»æ¢å¤åèå符串
- ç©ºç»æ¢å®½å符串
- std::char_traits
- 注é
- 容å¨åº
- è¿ä»£å¨åº
- èå´åº (C++20)
- ç®æ³åº
- æ°å¼åº
- è¾å ¥/è¾åºåº
- æä»¶ç³»ç»åº
- æ¬å°ååº
- æ£å表达å¼åº
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- å®éªæ§ C++ ç¹æ§
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- std 符å·ç´¢å¼
- åç¨æ¯æ (C++20)
- C++ å ³é®è¯
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std::basic_string<CharT,Traits,Allocator>::assign
basic_string& assign( const T& t,
(C++20 å)
template < class T >
constexpr basic_string& assign( const T& t,
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| s | - | æåç¨ä½æºåå§å string å符串çæé |
| ilist | - | ç¨ä»¥åå§å string å符ç std::initializer_list |
| sv | - | ç¨ä»¥åå§å string å符ç std::basic_string_view |
| t | - | ç¨ä»¥åå§å string å符ç对象ï¼å¯è½¬æ¢ä¸º std::basic_string_view ï¼ |
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noexcept è§å®ï¼Â Â
noexcept(std::allocator_traits<Allocator>::propagate_on_container_move_assignment::value  || std::allocator_traits<Allocator>::is_always_equal::value) |
(C++17 èµ·) |
示ä¾
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#include <iostream> #include <iterator> #include <string> Â int main() { std::string s; // assign(size_type count, CharT ch) s.assign(4, '='); std::cout << s << '\n'; // "====" Â std::string const c("Exemplary"); // assign(basic_string const& str) s.assign(c); std::cout << c << "==" << s <<'\n'; // "Exemplary == Exemplary" Â // assign(basic_string const& str, size_type pos, size_type count) s.assign(c, 0, c.length()-1); std::cout << s << '\n'; // "Exemplar"; Â // assign(basic_string&& str) s.assign(std::string("C++ by ") + "example"); std::cout << s << '\n'; // "C++ by example" Â // assign(charT const* s, size_type count) s.assign("C-style string", 7); std::cout << s << '\n'; // "C-style" Â // assign(charT const* s) s.assign("C-style\0string"); std::cout << s << '\n'; // "C-style" Â char mutable_c_str[] = "C-style string"; // assign(InputIt first, InputIt last) s.assign(std::begin(mutable_c_str), std::end(mutable_c_str)-1); std::cout << s << '\n'; // "C-style string" Â // assign(std::initializer_list<charT> ilist) s.assign({ 'C', '-', 's', 't', 'y', 'l', 'e' }); std::cout << s << '\n'; // "C-style" }
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==== Exemplary==Exemplary Exemplar C++ by example C-style C-style C-style string C-style
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| DR | åºç¨äº | åºçæ¶çè¡ä¸º | æ£ç¡®è¡ä¸º |
|---|---|---|---|
| LWG 2063 | C++11 | éæ ååæ³¨éæ¾è¯´äº¤æ¢æ¯ç§»å¨èµå¼çåæ³å®ç° | æ´æ£ä¸ºè¦æ±ç§»å¨èµå¼ |
| LWG 2579 | C++11 | assign(const basic_string&) ä¸ä¼ æåé
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| LWG 2946 | C++17 | string_view éè½½å¨æäºæ
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