Hi,
Here's more trouble I'm having. It's again a problem with checking to see whether or not an integer has been entered, and how to deal with it. I've tried advice taken from
an earlier thread of mine (retired now), and also
that page Zahlman finds useful.
It's still a lottery simulator I'm trying to do. But I'm having trouble determining whether or not the supplied input is an integer or not. Here's the relevant code I have at the moment:
#include <iostream>
#include <iomanip>
#include <ctime>
#include <cstdlib>
#include <list>
#include <limits>
#include <string>
std::list<int> InputNumbers; // Player input numbers
std::list<int>::iterator InputCounter; // Player's list iterator
void GetNumbers()
{
int Input;
while(InputNumbers.size()<6)
{
int Remaining=6-InputNumbers.size();
std::cout<<std::setw(10)<<"\n\nEnter a number between 1 and 49. "<<Remaining<<" numbers still need to be chosen. ";
if(!(std::cin>>Input))
{
std::cin.sync();
std::cout<<"\nPlease enter a valid number.";
std::cin.clear();
}
InputNumbers.push_back(Input);
}
std::cout<<"\n";
for(InputCounter=InputNumbers.begin();InputCounter!=InputNumbers.end();InputCounter++)
{
std::cout<<*InputCounter<<"\n";
}
//int NumberInputs;
}
The behaviour is a little bizarre. I use this as test data:
1m3
33
m55
1s2
m2i3
2s6g
The letters are there to test the robustness of the input handler.
As you can see, the theory is that if the input is invalid (i.e. not an integer), there should be some kind of error handling going on. Thing is, the cin buffer is read one character at a time, so using my test data gives me this:
As you can see, the buffer isn't clearing properly, and the results are listed at the bottom. I can't see a way round this behaviour.
Hacking around with the test data sometimes leads to list elements holding the value -83029409 etc.
I know I could use std::getline(), but all that did was put 0 into the list element if the input was invalid.
This is really irritating, actually. If any of you have any ideas about how to hack around this, I'd love to hear them.
Thanks for your help,
ukdeveloper.
