public member function
<string>

std::basic_string::push_back

void push_back (charT c);
Append character to string
Appends character c to the end of the basic_string, increasing its length by one.

Parameters

c
Character added to the basic_string.
charT is basic_string's character type (i.e., its first template parameter).

Return value

none

Example

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// string::push_back
#include <iostream>
#include <fstream>
#include <string>

int main ()
{
  std::string str;
  std::ifstream file ("test.txt",std::ios::in);
  if (file) {
    while (!file.eof()) str.push_back(file.get());
  }
  std::cout << str << '\n';
  return 0;
}


This example reads an entire file character by character, appending each character to a string object using push_back.

Complexity

Unspecified; Generally amortized constant, but up to linear in the new string length.

Iterator validity

Any iterators, pointers and references related to this object may be invalidated.

Data races

The object is modified.

Exception safety

Strong guarantee: if an exception is thrown, there are no changes in the basic_string.

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