infinite while loop

[codenamejupiterx]

my intension is to have an input that would not accept characters. But for some reason my while loop wont stop to let the try again. It just runs on....



cin>>answer;
while (!isdigit(answer))
{
cout<<"not a number,try again";
cin>>answer;
}

[hamsterman]

If answer is a char, this should work (almost) fine.

[Ikaron]

I have a feeling that 'answer' is an int, which can cause problems if you put in a char, and in that case you'll want to do something like this each time through:

if (cin.fail())
{
	cin.clear();
	cin.ignore(INT_MAX, '\n');
}

[zb0S216C]

This works:

int iAnswer( 0 );

while( true )
{
    std::cin.sync( );
    std::cin >> iAnswer;
    if( !std::cin.good( ) )
    {
        std::cin.clear( );
        std::cout << "That's not a number" << std::endl;              
    }

    else
        std::cout << "That's a number" << std::endl;
}

_Wazzak