c++不使用C标准库将字符串和int转换为char *

Question

not using the C standard library do this in C++ ?

1. 将字符串转换为char*
2. 将int转换为char*

如果我必须在 C++ 中将字符串转换为 int，请使用类似这样的东西

#include<iostream>
#include<string>
#include<sstream>
using namespace std;
int main()
{
    int num;
    string str="2020";
    (stringstream)"2020">>num;
    cout<<num+2;
    return 0;
}

Answer 1

#include <sstream>
#include <iostream>
#include <string>

int main (int argc, char* argv[])
{
    std::string str ("123");
    const char* c_str = str.c_str();

    char* so_bad = const_cast<char*>(c_str);

    std::stringstream ss;
    ss << so_bad;

    int int_value;
    ss >> int_value;

    std::cout << int_value;

    return 0;
}