如何在C++中将字符串转换为double？

#include<iostream>
#include<string>
#include <stdexcept>

int main() {
    std::string str_num = "3.14";
    try {
        double num = std::stod(str_num);
        std::cout << "字符串转换为double: "<< num<< std::endl;
    } catch (std::invalid_argument &e) {
        std::cout << "无效的输入: " << e.what()<< std::endl;
    } catch (std::out_of_range &e) {
        std::cout << "超出范围的输入: " << e.what()<< std::endl;
    }
    return 0;
}