basic_string&insert(size_typeindex,size_typecount,CharTch); (1) (constexpr since C++20)basic_string&insert(size_typeindex,constCharT*s); (2) (constexpr since C++20)basic_string&insert(size_typeindex,constCharT*s,size_typecount); (3) (constexpr since C++20)basic_string&insert(size_typeindex,constbasic_string&str); (4) (constexpr since C++20)basic_string&insert(size_typeindex,constbasic_string&str,size_types_index,size_typecount); (5)(until C++14)basic_string&insert(size_typeindex,constbasic_string&str,size_types_index,size_typecount=npos);(since C++14)
(constexpr since C++20)iteratorinsert(iteratorpos,CharTch); (6)(until C++11)iteratorinsert(const_iteratorpos,CharTch);(since C++11)
(constexpr since C++20)voidinsert(iteratorpos,size_typecount,CharTch); (7)(until C++11)iteratorinsert(const_iteratorpos,size_typecount,CharTch);(since C++11)
(constexpr since C++20)template<classInputIt>voidinsert(iteratorpos,InputItfirst,InputItlast); (8)(until C++11)template<classInputIt>iteratorinsert(const_iteratorpos,InputItfirst,InputItlast);(since C++11)
(constexpr since C++20)iteratorinsert(const_iteratorpos,std::initializer_list<CharT>ilist); (9) (since C++11)
(constexpr since C++20)template<classStringViewLike>basic_string&insert(size_typeindex,constStringViewLike&t); (10) (since C++17)
(constexpr since C++20)template<classStringViewLike>basic_string&insert(size_typeindex,constStringViewLike&t,size_typet_index,size_typecount=npos); (11) (since C++17)
(constexpr since C++20)Inserts characters into the string.
1) Inserts count copies of character ch at the position index.
2) Inserts null-terminated character string pointed to by s at the position index. The length of the string is determined by the first null character using Traits::length(s).
3) Inserts the characters in the range [s, s+count) at the position index. The range can contain null characters.
4) Inserts string str at the position index.
5) Inserts a string, obtained by str.substr(s_index,count) at the position index.
6) Inserts character ch before the character pointed by pos.
7) Inserts count copies of character ch before the element (if any) pointed by pos.
8) Inserts characters from the range [first, last) before the element (if any) pointed by pos, as if by insert(pos-begin(),basic_string(first,last,get_allocator())).
This overload does not participate in overload resolution if InputIt does not satisfy
.
(since C++11)9) Inserts elements from initializer list ilist before the element (if any) pointed by pos.
10) Implicitly converts t to a string view sv as if by std::basic_string_view<CharT,Traits>sv=t;, then inserts the elements from sv before the element (if any) pointed by index, as if by insert(index,sv.data(),sv.size()).
This overload participates in overload resolution only if std::is_convertible_v<constStringViewLike&,std::basic_string_view<CharT,Traits>> is true and std::is_convertible_v<constStringViewLike&,constCharT*> is false.
11) Implicitly converts t to a string view sv as if by std::basic_string_view<CharT,Traits>sv=t;, then inserts, before the element (if any) pointed by index, the characters from the subview [t_index, t_index+count) of sv.
If the requested subview lasts past the end of sv, or if count==npos, the resulting subview is [t_index, sv.size()).
If t_index>sv.size(), or if index>size(),
is thrown.
This overload participates in overload resolution only if std::is_convertible_v<constStringViewLike&,std::basic_string_view<CharT,Traits>> is true and std::is_convertible_v<constStringViewLike&,constCharT*> is false.
If pos is not a valid iterator on *this, the behavior is undefined.
Parameters
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 s_index - position of the first character in str to insert ilist -
to insert the characters from t - object (convertible to
) to insert the characters from t_index - position of the first character in t to insert Type requirements -InputIt must meet the requirements of
. Return value
1-5)*this
6-9) An iterator which refers to the copy of the first inserted character or pos if no characters were inserted (count==0 or first==last or ilist.size()==0)
10,11)*this
Exceptions
5) Throws
if index>size() or if s_index>str.size().
11) Throws
if index>size() or if t_index>sv.size().
In all cases, throws
if size()+ins_count>max_size() where ins_count is the number of characters that will be inserted.
In all cases, if std::allocator_traits<Allocator>::allocate throws an exception, it is rethrown.
(since C++20)If an exception is thrown for any reason, this function has no effect (
strong exception safety guarantee
).
Example
Run this code
#include<cassert>#include<iterator>#include<string>usingnamespacestd::string_literals;intmain(){std::strings="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 s_index, 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::stringseq=" 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);}Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR Applied to Behavior as published Correct behavior
C++98 overload (8) referred to a non-existing overload refers to overload (4) correctly
C++98 there was no exception safety guarantee added strong exception safety guarantee
C++17 overload (10) caused ambiguity in some cases avoided by making it a template See also