NAME¶

std::basic_string::copy - std::basic_string::copy

Synopsis¶

size_type copy( CharT* dest, size_type count, size_type pos = 0 ) (until C++20)
const;
constexpr size_type copy( CharT* dest, size_type count, size_type pos (since C++20)
= 0 ) const;

Copies a substring [pos, pos+count) to character string pointed to by dest. If the
requested substring lasts past the end of the string, or if count == npos, the
copied substring is [pos, size()). The resulting character string is not
null-terminated.

If pos > size(), std::out_of_range is thrown.

Parameters¶

dest - pointer to the destination character string
count - length of the substring
pos - position of the first character to include

Return value¶

number of characters copied

Exceptions¶

std::out_of_range if pos > size().

Complexity¶

linear in count

Example¶

// Run this code

#include <string>
#include <iostream>

int main()
{
std::string foo("quuuux");
char bar[7]{};
foo.copy(bar, sizeof bar);
std::cout << bar << '\n';
}

Output:¶

quuuux

See also¶

substr returns a substring
(public member function)
copy copies characters
(C++17) (public member function of std::basic_string_view<CharT,Traits>)
copy copies a range of elements to a new location
copy_if (function template)
(C++11)
memcpy copies one buffer to another
(function)