std::basic_string::insert

basic_string& insert( size_type index, size_type count, CharT ch );	(1)
basic_string& insert( size_type index, const CharT* s );	(2)
basic_string& insert( size_type index, const CharT* s, size_type count );	(3)
basic_string& insert( size_type index, const basic_string& str );	(4)
	(5)
basic_string& insert( size_type index, const basic_string& str, size_type index_str, size_type count );	(until C++14)
basic_string& insert( size_type index, const basic_string& str, size_type index_str, size_type count = npos);	(since C++14)
	(6)
iterator insert( iterator pos, CharT ch );	(until C++11)
iterator insert( const_iterator pos, CharT ch );	(since C++11)
	(7)
void insert( iterator pos, size_type count, CharT ch );	(until C++11)
iterator insert( const_iterator pos, size_type count, CharT ch );	(since C++11)
	(8)
template< class InputIt > void insert( iterator pos, InputIt first, InputIt last );	(until C++11)
template< class InputIt > iterator insert( const_iterator pos, InputIt first, InputIt last );	(since C++11)
iterator insert( const_iterator pos, std::initializer_list<CharT> ilist );	(9)	(since C++11)
basic_string& insert( size_type pos, basic_string_view<CharT, Traits> sv );	(10)	(since C++17)
template < class T > basic_string& insert( size_type index, const T& t, size_type index_str, size_type count = npos);	(11)	(since C++17)

将字符插入字符串。

1%29次插入count字符副本ch在这个位置index

2%29插入以空结尾的字符串。s在这个位置index字符串的长度由第一个空字符%28有效调用决定Traits::length(s)...

3%29插入第一个count指向的字符串中的字符。s在这个位置index...s可以包含空字符。

4%29插入字符串str在这个位置index

5%29插入字符串，由str.substr(index_str, count)在这个位置index

6%29插入字符ch之前的字符pos

7%29次插入count字符副本ch在由pos

8%29插入范围内的字符。[first, last)在由pos此重载不参与重载解决方案。InputIt不满意InputIterator.%28自C++11%29

9%29从初始化程序列表插入元素ilist在由pos

10%29从字符串视图插入元素。sv在由pos，好像insert(pos, sv.data(), sv.size())

11%29名皈依者t到字符串视图sv好像std::basic_string_view<CharT, Traits> sv = t;，然后插入pos，子视图中的字符。[index_str, index_str+count)成sv如果所请求的子视图持续到sv，或者如果count == npos，生成的子视图是[index_str, sv.size()).如果index_str > sv.size()，或者如果index > size()，，，std::out_of_range被扔了。此重载只参与在下列情况下的重载解决方案：std::is_convertible_v<const T&,std::basic_string_view<CharT, Traits>>是true和std::is_convertible_v<const T&, const CharT*>是false...

参数

index	-	position at which the content will be inserted
pos	-	iterator before which the characters will be inserted
ch	-	character to insert
count	-	number of characters to insert
s	-	pointer to the character string to insert
str	-	string to insert
first, last	-	range defining characters to insert
index_str	-	position of the first character in the string str to insert
ilist	-	std::initializer_list to insert the characters from
sv	-	std::basic_string_view to insert the characters from
t	-	object (convertible to std::basic_string_view) to insert the characters from

类型要求

-输入必须符合输入器的要求。

返回值

1-5，10-11%29*this

6-9%29一个迭代器，它指的是第一个插入字符的副本或pos如果没有插入字符%28count==0或first==last或ilist.size()==0%29

例外

1%29std::out_of_range如果index > size()和std::length_error如果size() + count > max_size()...

2%29std::out_of_range如果index > size()和std::length_error如果size() + Traits::length(s) > max_size()...

3%29std::out_of_range如果index > size()和std::length_error如果size() + count > max_size()...

4%29std::out_of_range如果index > size()和std::length_error如果size() + str.size() > max_size()...

5%29在下列条件下抛出异常：

A%29std::out_of_range如果index > size()...

B%29std::out_of_range如果index_str > str.size()...

C%29std::length_error如果size() + ins_count > max_size()何地ins_count要插入的字符数。

6-9%29%280%29

10%29std::out_of_range如果index > size()和std::length_error如果size() + sv.size() > max_size()...

11%29在下列条件下抛出异常：

A%29std::out_of_range如果index > size()...

B%29std::out_of_range如果index_str > sv.size()...

C%29std::length_error如果size() + ins_count > max_size()何地ins_count要插入的字符数。

In any case, if an exception is thrown for any reason, this function has no effect (strong exception guarantee).	(since C++11)

例

二次

#include <cassert>
#include <iterator>
#include <string>
using namespace std::string_literals;
int main()
{
    std::string s = "xmplr";
 
    // insert(size_type index, size_type count, char ch)
    s.insert(0, 1, 'E');
    assert("Exmplr" == s);
 
    // insert(size_type index, const char* s)
    s.insert(2, "e");
    assert("Exemplr" == s);
 
    // insert(size_type index, string const& str)
    s.insert(6, "a"s);
    assert("Exemplar" == s);
 
    // insert(size_type index, string const& str,
    //     size_type index_str, size_type count)
    s.insert(8, " is an example string."s, 0, 14);
    assert("Exemplar is an example" == s);
 
    // insert(const_iterator pos, char ch)
    s.insert(s.cbegin() + s.find_first_of('n') + 1, ':');
    assert("Exemplar is an: example" == s);
 
    // insert(const_iterator pos, size_type count, char ch)
    s.insert(s.cbegin() + s.find_first_of(':') + 1, 2, '=');
    assert("Exemplar is an:== example" == s);
 
    // insert(const_iterator pos, InputIt first, InputIt last)
    {
        std::string seq = " string";
        s.insert(s.begin() + s.find_last_of('e') + 1,
            std::begin(seq), std::end(seq));
        assert("Exemplar is an:== example string" == s);
    }
 
    // insert(const_iterator pos, std::initializer_list<char>)
    s.insert(s.cbegin() + s.find_first_of('g') + 1, { '.' });
    assert("Exemplar is an:== example string." == s);
}

二次

另见

append	appends characters to the end (public member function)
push_back	appends a character to the end (public member function)

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最后更新于：2017-12-18