std::operator+(std::basic_string)

 

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类

basic_string

basic_string_view (C++17)

char_traits

 

std::basic_string

成员函数 basic_string::basic_string basic_string::operator= basic_string::assign basic_string::get_allocator 元素访问 basic_string::at basic_string::operator[] basic_string::front (C++11) basic_string::back (C++11) basic_string::data basic_string::c_str basic_string::operator basic_string_view (C++17) 迭代器 basic_string::beginbasic_string::cbegin (C++11) basic_string::endbasic_string::cend (C++11) basic_string::rbeginbasic_string::crbegin (C++11) basic_string::rendbasic_string::crend (C++11) 容量 basic_string::empty basic_string::sizebasic_string::length basic_string::max_size basic_string::reserve basic_string::capacity basic_string::shrink_to_fit (C++11)

操作 basic_string::clear basic_string::insert basic_string::erase basic_string::push_back basic_string::pop_back (C++11) basic_string::append basic_string::operator+= basic_string::compare basic_string::starts_with (C++20) basic_string::ends_with (C++20) basic_string::replace basic_string::substr basic_string::copy basic_string::resize basic_string::swap 查找 basic_string::find basic_string::rfind basic_string::find_first_of basic_string::find_first_not_of basic_string::find_last_of basic_string::find_last_not_of 常量 basic_string::npos

非成员函数 operator+ operator==operator!=operator<operator>operator<=operator>= swap(std::basic_string) operator<<operator>> getline stoistolstoll (C++11) (C++11) (C++11) stoulstoull (C++11) (C++11) stofstodstold (C++11) (C++11) (C++11) to_string (C++11) to_wstring (C++11) operator""s (C++14) 辅助类 hash<std::string>hash<std::wstring>hash<std::u32string>hash<std::u16string> (C++11) (C++11) (C++11) (C++11) 推导指引(C++17)

 

template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+( const basic_string<CharT,Traits,Alloc>& lhs,                    const basic_string<CharT,Traits,Alloc>& rhs );	(1)
template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+( const CharT* lhs,                    const basic_string<CharT,Traits,Alloc>& rhs );	(2)
template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+( CharT lhs,                    const basic_string<CharT,Traits,Alloc>& rhs );	(3)
template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+( const basic_string<CharT,Traits,Alloc>& lhs,                    const CharT* rhs );	(4)
template<class CharT, class Traits, class Alloc>     basic_string<CharT,Traits,Alloc>         operator+( const basic_string<CharT,Traits,Alloc>& lhs,                    CharT rhs );	(5)
template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+( basic_string<CharT,Traits,Alloc>&& lhs,                    const basic_string<CharT,Traits,Alloc>& rhs );	(6)	(C++11 起)
template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+( const basic_string<CharT,Traits,Alloc>& lhs,                    basic_string<CharT,Traits,Alloc>&& rhs );	(7)	(C++11 起)
template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+( basic_string<CharT,Traits,Alloc>&& lhs,                    basic_string<CharT,Traits,Alloc>&& rhs );	(8)	(C++11 起)
template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+(const CharT* lhs,                   basic_string<CharT,Traits,Alloc>&& rhs );	(9)	(C++11 起)
template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+( CharT lhs,                    basic_string<CharT,Traits,Alloc>&& rhs );	(10)	(C++11 起)
template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+( basic_string<CharT,Traits,Alloc>&& lhs,                    const CharT* rhs );	(11)	(C++11 起)
template< class CharT, class Traits, class Alloc >     basic_string<CharT,Traits,Alloc>         operator+( basic_string<CharT,Traits,Alloc>&& lhs,                    CharT rhs );	(12)	(C++11 起)

返回由含来自 lhs 的字符后随来自 rhs 字符的字符串。

参数

lhs	-	string 、字符或指向空终止数组的首字符的指针
rhs	-	string 、字符或指向空终止数组的首字符的指针

返回值

1) basic_string<CharT,Traits,Alloc>(lhs).append(rhs)

2) basic_string<CharT,Traits,Alloc>(lhs) + rhs

3) basic_string<CharT,Traits,Alloc>(1,lhs) + rhs

4) lhs + basic_string<CharT,Traits,Alloc>(rhs)

5) lhs + basic_string<CharT,Traits,Alloc>(1,rhs)

6) std::move(lhs.append(rhs))

7) std::move(rhs.insert(0, lhs))

8) std::move(lhs.append(rhs)) 或 std::move(rhs.insert(0, lhs))

9) std::move(rhs.insert(0, lhs))

10) std::move(rhs.insert(0, 1, lhs))

11) std::move(lhs.append(rhs))

12) std::move(lhs.append(1, rhs))

示例

运行此代码

#include <iostream>
#include <string>
 
int main()
{
    std::string s1 = "Hello";
    std::string s2 = "world";
    std::cout << s1 + ' ' + s2 + "!\n";
}

输出：

Hello world!

参阅

operator+=	后附字符到结尾 (公开成员函数)
append	后附字符到结尾 (公开成员函数)
insert	插入字符 (公开成员函数)