std::basic_string::append

 

C++

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Standard library headers

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Utilities library

Strings library

Containers library

Algorithms library

Iterators library

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Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

 

Strings library

Null-terminated strings

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Classes

basic_string

char_traits

 

std::basic_string

Member functions basic_string::basic_string basic_string::operator= basic_string::assign basic_string::get_allocator Element access basic_string::at basic_string::operator[] basic_string::front (C++11) basic_string::back (C++11) basic_string::data basic_string::c_str Iterators 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) Capacity 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)

Operations 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::replace basic_string::substr basic_string::copy basic_string::resize basic_string::swap Search 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 Constants basic_string::npos

Non-member functions 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) Helper classes hash<std::string>hash<std::wstring>hash<std::u32string>hash<std::u16string> (C++11)

 

basic_string& append( size_type count, CharT ch );	(1)
basic_string& append( const basic_string& str );	(2)
	(3)
basic_string& append( const basic_string& str,                       size_type pos,                       size_type count );			(until C++14)
basic_string& append( const basic_string& str,                       size_type pos,                       size_type count = npos);			(since C++14)
basic_string& append( const CharT* s,                       size_type count );		(4)
basic_string& append( const CharT* s );		(5)
template< class InputIt > basic_string& append( InputIt first, InputIt last );		(6)
basic_string& append( std::initializer_list<CharT> ilist );		(7)	(since C++11)

Appends additional characters to the string.

1) Appends count copies of character ch

2) Appends string str

3) Appends a substring [pos, pos+count) of str. If the requested substring lasts past the end of the string, or if count == npos, the appended substring is [pos, size()). If pos >= str.size(), std::out_of_range is thrown.

4) Appends the first count characters of character string pointed to by s. s can contain null characters.

5) Appends the null-terminated character string pointed to by s. The length of the string is determined by the first null character.

6) Appends characters in the range [first, last). This overload does not participate in overload resolution if InputIt does not satisfy InputIterator. (since C++11)

7) Appends characters in the initializer list ilist.

Parameters

count	-	number of characters to append
ch	-	character value to append
first, last	-	range of characters to append
str	-	string to append
s	-	pointer to the character string to append
ilist	-	initializer list with the characters to append
Type requirements
- InputIt must meet the requirements of InputIterator.

Return value

*this

Complexity

1) linear in count

2) linear in size of str

3-4) linear in count

5) linear in size of s

6) linear in distance between first and last

7) linear in size of ilist

Exceptions

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

If the operation would result in size() > max_size(), throws std::length_error.

Example

Run this code

#include <string>
#include <iostream>
 
int main() {
    std::basic_string<char> str = "string";
    const char* cptr = "C-string";
    const char carr[] = "Two and one";
 
    std::string output;
 
    // 1) Repeat a char
    output.append(3, '*');
    std::cout << "1) " << output << "\n";
 
    //  2) Append a whole string
    output.append(str);
    std::cout << "2) " << output << "\n";
 
    // 3) Append part of a string (last 3 letters, in this case)
    output.append(str, 3, 3);
    std::cout << "3) " << output << "\n";
 
    // 4) Append part of a C-string
    // Notice, because `append` returns *this, we can chain calls together
    output.append(1, ' ').append(carr, 4);
    std::cout << "4) " << output << "\n";
 
    // 5) Append a whole C-string
    output.append(cptr);
    std::cout << "5) " << output << "\n";
 
    // 6) Append range
    output.append(&carr[3], std::end(carr));
    std::cout << "6) " << output << "\n";
 
    // 7) Append initializer list
    output.append({ ' ', 'l', 'i', 's', 't' });
    std::cout << "7) " << output << "\n";
}

Output:

1) ***
2) ***string
3) ***stringing
4) ***stringing Two 
5) ***stringing Two C-string
6) ***stringing Two C-string and one
7) ***stringing Two C-string and one list

See also

operator+=

appends characters to the end (public member function)