std::basic_string::operator[]
性病：基本[医]字符串：操作符。[]
| reference operator; | (1) | |
|---|---|---|
| const_reference operator const; | (2) | |
返回对指定位置的字符的引用。pos.不执行边界检查。
| 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 pos == size(), a reference to the character with value CharT() (the null character) is returned. For the first (non-const) version, the behavior is undefined if this character is modified to any value other than charT(). | (since C++11) |
参数
| pos | - | position of the character to return |
|---|
返回值
引用请求的字符。
复杂性
常量。
例
二次
#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';
std::cout << s << '\n';
}
二次
产出：
二次
rmx
Exemplar
Exemplary
二次
另见
| at | access specified character with bounds checking (public member function) |
|---|
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