itoa replace to std::to_string how to

Question

How can i replace this

    itoa(i, buf, 10);
    key1.append(buf);
    key2.append(buf);
    key3.append(buf);

with std::to_string

itoa was giving me an error it was not declared in scope that its not part of standard

I heard i can use std::to_string to make another version of it how do i do this?

Here's a [reference](http://en.cppreference.com/w/cpp/string/basic_string/to_string). It even includes an example. — chris, Dec 10 '12 at 05:02
What exactly is the problem? Doesn't `std::to_string(i)` solve it? Is the problem that this creates a `std::string`, but you need a `char *`? — jogojapan, Dec 10 '12 at 05:43
Yes, `std::to_string` only exists in C++11. If you are looking for a solution that works with C++98/03, you can't use `std::to_string`. `boost::lexical_cast` is often recommended as alternative (but requires that you include the relevant headers from the Boost library). And of course `std::ostringstream` as mentioned in the answers is another alternative. — jogojapan, Dec 10 '12 at 07:33

score 4 · Accepted Answer · answered Dec 10 '12 at 07:29

If you use C++11, you can use std::to_string

#include <string>
std::string buf = std::to_string(i);
key1.append(buf);
key2.append(buf);
key3.append(buf);

or you could just use std:stringstream

#include <sstream>
std::stringstream ss;
ss << i;
key1.append(ss.str());
key2.append(ss.str());
key3.append(ss.str());

score -1 · Answer 2 · answered Dec 10 '12 at 06:56

-1

To use itoa() function, you need to include stdlib.h file, then you will not see the error while using itoa().

answered Dec 10 '12 at 06:56

Rock

2

As the question says, `itoa` isn't part of the standard and may not be available; in which case, you will get the error. – Mike Seymour Dec 10 '12 at 07:56

2 Answers2