[SOLVED] C++ input validation help

[meton_magis]

Hey,

I'm trying to make a function to validate that integral values were entered on stdin.
here is what I have.

template <typename type>
void getSaneNumber(type &number)
{
  number = 0;
  number += 0;  // make sure template is used for only numbers, or compatible
  std::string input;
  std::getline(std::cin, input, '\n');

  while (!(atof(input.c_str())))
  {
    std::cerr << "Invalid input, try again: " << std::flush;
    std::getline(std::cin, input, '\n');
  }

  number = atof(input.c_str());
};

My problem is that due to the `while (!( atof(input.c_str())))` part, the function will not work if the input is 0.

Anyone see a way of getting around this? If you have a suggestion for a better function to validate input as an integer (or float) then I'm open to suggestion, I just haven't seen anything better from googling.

Thanks

[meton_magis]

Well I stumbled upon the answer I needed. I changed it to

template <typename type>
void getSaneNumber(type &number)
{
  number = 0;
  number += 0;  
  while (!(std::cin >> number))
  {
    std::cerr << "Invalid input, try again: " << std::flush;
    std::cin.clear();
    std::cin.ignore(std::numeric_limits<std::streamsize>::max(),'\n');
  }
};

and the loop condition is true if cin gets any non numeric input, but will stop looping if somone enters 0.


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