std::basic_string::replace

C++

Language

Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Algorithms library

Iterators library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

Strings library

Null-terminated strings

Byte strings

Multibyte strings

Wide strings

Classes

basic_string

basic_string_view (C++17)

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 basic_string::operator basic_string_view (C++17) 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::starts_with (C++20) basic_string::ends_with (C++20) 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) operator""s (C++14) Helper classes hash<std::string>hash<std::wstring>hash<std::u32string>hash<std::u16string> (C++11)(C++11)(C++11)(C++11) hash<std::pmr::string>hash<std::pmr::wstring>hash<std::pmr::u32string>hash<std::pmr::u16string> (C++20)(C++20)(C++20)(C++20) Deduction guides(C++17)

basic_string& replace( size_type pos, size_type count, const basic_string& str );	(1)
basic_string& replace( const_iterator first, const_iterator last, const basic_string& str );	(1)
	(2)
basic_string& replace( size_type pos, size_type count, const basic_string& str, size_type pos2, size_type count2 );			(until C++14)
basic_string& replace( size_type pos, size_type count, const basic_string& str, size_type pos2, size_type count2 = npos );			(since C++14)
template< class InputIt > basic_string& replace( const_iterator first, const_iterator last, InputIt first2, InputIt last2 );		(3)
basic_string& replace( size_type pos, size_type count, const CharT* cstr, size_type count2 );		(4)
basic_string& replace( const_iterator first, const_iterator last, const CharT* cstr, size_type count2 );		(4)
basic_string& replace( size_type pos, size_type count, const CharT* cstr );		(5)
basic_string& replace( const_iterator first, const_iterator last, const CharT* cstr );		(5)
basic_string& replace( size_type pos, size_type count, size_type count2, CharT ch );		(6)
basic_string& replace( const_iterator first, const_iterator last, size_type count2, CharT ch );		(6)
basic_string& replace( const_iterator first, const_iterator last, std::initializer_list<CharT> ilist );		(7)	(since C++11)
template < class T > basic_string& replace( size_type pos, size_type count, const T& t );		(8)	(since C++17)
template < class T > basic_string& replace( const_iterator first, const_iterator last, const T& t );		(8)	(since C++17)
template < class T > basic_string& replace( size_type pos, size_type count, const T& t, size_type pos2, size_type count2 = npos );		(9)	(since C++17)

Replaces the part of the string indicated by either [pos, pos + count) or [first, last) with a new string.

The new string can be one of:

1) string str;

2) substring [pos2, pos2 + count2) of str, except if count2==npos or if would extend past str.size(), [pos2, str.size()) is used.

3) characters in the range [first2, last2). This overload has the same effect as overload (6) if InputIt is an integral type.

4) first count2 characters of the character string pointed to by cstr;

5) null-terminated character string pointed to by cstr;

6) count2 copies of character ch;

7) characters in the initializer list ilist;

8) characters of a string view sv, converted from t as if by std::basic_string_view<CharT, Traits> sv = t;. These overloads only participate in overload resolution if std::is_convertible_v<const T&, std::basic_string_view<CharT, Traits>> is true and std::is_convertible_v<const T&, const CharT*> is false

9) subview [pos2, pos2 + count2) of a string view sv, converted from t as if by std::basic_string_view<CharT, Traits> sv = t;, except if count2==npos or if it would extend past sv.size(), [pos2, sv.size()) is used. This overload only participates in overload resolution if std::is_convertible_v<const T&, std::basic_string_view<CharT, Traits>> is true and std::is_convertible_v<const T&, const CharT*> is false.

Parameters

pos	-	start of the substring that is going to be replaced
count	-	length of the substring that is going to be replaced
first, last	-	range of characters that is going to be replaced
str	-	string to use for replacement
pos2	-	start of the substring to replace with
count2	-	number of characters to replace with
cstr	-	pointer to the character string to use for replacement
ch	-	character value to use for replacement
first2, last2	-	range of characters to use for replacement
ilist	-	initializer list with the characters to use for replacement
t	-	object (convertible to std::basic_string_view) with the characters to use for replacement

Return value

*this

Exceptions

std::out_of_range if pos > length() or pos2 > str.length()

std::length_error if the resulting string will exceed maximum possible string length (std::string::npos - 1)

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

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 2946	C++17	string_view overload causes ambiguity in some cases	avoided by making it a template

Example

Run this code

#include <iostream>
#include <string>

int main()
{
    std::string str("The quick brown fox jumps over the lazy dog.");

    str.replace(10, 5, "red"); // (5)

    str.replace(str.begin(), str.begin() + 3, 1, 'A'); // (6)

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

Output:

A quick red fox jumps over the lazy dog.