(1) string

Inserts a copy of str.

(2) substring

Inserts a copy of a substring of str. The substring is the portion of str that begins at the character position subpos and spans sublen characters (or until the end of str, if either str is too short or if sublen is npos).

(3) c-string

Inserts a copy of the string formed by the null-terminated character sequence (C-string) pointed by s.
The length of this character sequence is determined by calling traits_type::length(s).

(4) buffer

Inserts a copy of the first n characters in the array of characters pointed by s.

(5) fill

Inserts n consecutive copies of character c.

(6) single character

Inserts character c.

(7) range

Inserts a copy of the sequence of characters in the range [first,last), in the same order.

(8) initializer list

Inserts a copy of each of the characters in il, in the same order.

Parameters

pos

Insertion point: The new contents are inserted before the character at position pos.
If this is greater than the object's length, it throws out_of_range.
Note: The first character is denoted by a value of 0 (not 1).

str

Another basic_string object of the same type (with the same class template arguments charT, traits and Alloc).

subpos

Position of the first character in str that is inserted into the object as a substring.
If this is greater than str's length, it throws out_of_range.
Note: The first character in str is denoted by a value of 0 (not 1).

sublen

Length of the substring to be copied (if the string is shorter, as many characters as possible are copied).
A value of npos indicates all characters until the end of str.

s

Pointer to an array of characters (such as a c-string).

n

Number of characters to insert.

c

Character value.

p

Iterator pointing to the insertion point: The new contents are inserted before the character pointed by p.
iterator is a member type, defined as a random access iterator type that points to characters of the basic_string.

first, last

Input iterators to the initial and final positions in a range. The range used is [first,last), which includes all the characters between first and last, including the character pointed by first but not the character pointed by last.
The function template argument InputIterator shall be an input iterator type that points to elements of a type convertible to charT.

il

An initializer_list object.
These objects are automatically constructed from initializer list declarators.

Return value

Member type

Example

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// inserting into a string
#include <iostream>
#include <string>

int main ()
{
  std::string str="to be question";
  std::string str2="the ";
  std::string str3="or not to be";
  std::string::iterator it;

  // used in the same order as described above:
  str.insert(6,str2);                 // to be (the )question
  str.insert(6,str3,3,4);             // to be (not )the question
  str.insert(10,"that is cool",8);    // to be not (that is )the question
  str.insert(10,"to be ");            // to be not (to be )that is the question
  str.insert(15,1,':');               // to be not to be(:) that is the question
  it = str.insert(str.begin()+5,','); // to be(,) not to be: that is the question
  str.insert (str.end(),3,'.');       // to be, not to be: that is the question(...)
  str.insert (it+2,str3.begin(),str3.begin()+3); // (or )

  std::cout << str << '\n';
  return 0;
}

to be, or not to be: that is the question...

Complexity

Iterator validity

Data races

Exception safety

If

If pos is greater than the string length, or if subpos is greater than str's length, an out_of_range exception is thrown.
If the resulting string length would exceed the max_size, a length_error exception is thrown.
If the type uses the default allocator, a bad_alloc exception is thrown if the function needs to allocate storage and fails.

See also

basic_string::append

Append to string (public member function)

basic_string::replace

Replace portion of string (public member function)

basic_string::substr

Generate substring (public member function)

basic_string::operator=

String assignment (public member function)

basic_string::operator+=

Append to string (public member function)