std::basic_string<CharT,Traits,Allocator>::operator[]
(1) | ||
reference operator[]( size_type pos ); |
(until C++20) | |
constexpr reference operator[]( size_type pos ); |
(since C++20) | |
(2) | ||
const_reference operator[]( size_type pos ) const; |
(until C++20) | |
constexpr const_reference operator[]( size_type pos ) const; |
(since C++20) |
Returns a reference to the character at specified location pos
. No bounds checking is performed. If pos > size()
, the behavior is undefined.
1) If pos == size() , the behavior is undefined. 2) If pos == size() , a reference to the character with value CharT() (the null character) is returned. |
(until C++11) |
If For the first (non-const) version, the behavior is undefined if this character is modified to any value other than |
(since C++11) |
Parameters
pos | - | position of the character to return |
Return value
Reference to the requested character.
Complexity
Constant.
Example
#include <iostream> #include <string> int main() { std::string const e("Exemplar"); for (unsigned i = e.length() - 1; i != 0; i /= 2) std::cout << e[i]; std::cout << '\n'; const char* c = &e[0]; std::cout << c << '\n'; // print as a C string //Change the last character of s into a 'y' std::string s("Exemplar "); s[s.size()-1] = 'y'; // equivalent to s.back() = 'y'; std::cout << s << '\n'; }
Output:
rmx Exemplar Exemplary
See also
accesses the specified character with bounds checking (public member function) |
|
(C++11)
|
accesses the first character (public member function) |
(C++11)
|
accesses the last character (public member function) |
(C++17)
|
accesses the specified character (public member function of std::basic_string_view<CharT,Traits> ) |
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