C++11 introduces std::stoi (and variants for each numeric type) and std::to_string, the counterparts of the C atoi and itoa but expressed in term of std::string. is therefore the shortest way I can think of. You can even omit naming the type, using the auto keyword: Note: see [string.conversions] (21.5 in n3242)
In C++11 there are some nice new convert functions from std::string to a number type. So instead of you can use where str is your number as std::string. There are version for all flavours of numbers: long stol(string), float stof(string), double stod(string),… see http://en.cppreference.com/w/cpp/string/basic_string/stol
There are multiple ways: String.valueOf(number) (my preference) “” + number (I don’t know how the compiler handles it, perhaps it is as efficient as the above) Integer.toString(number)
If you look at the Java documentation you’ll notice the “catch” is that this function can throw a NumberFormatException, which of course you have to handle: (This treatment defaults a malformed number to 0, but you can do something else if you like.) Alternatively, you can use an Ints method from the Guava library, which in combination with Java 8’s Optional, makes … Read more