What is the proper way of using cin.fail() for validating the input?

Question

There's a program where we are supposed to enter numbers via a while loop, and I want to quit the program by entering a "non-numerical" character. Could this be the code?

while (cin.fail())
{
  // block of code
}

Also, is there a special standard header for cin.fail()?

score 1 · Answer 1 · answered Jan 16 '21 at 00:18

1

There's no need to call cin.fail(). You can just do:

int n;
while (std::cin >> n)
{
    do_something_with_n (n);
}

Also, please don't spam tags. c++ plus the highest c++ version you have access to will suffice.

answered Jan 16 '21 at 00:18

Paul Sanders

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Thank you for the seemingly effective response! All right, I'll take the "spamming tags" advice into account. – john applesead Jan 16 '21 at 00:21
Hokay. I didn't mean to sound harsh. – Paul Sanders Jan 16 '21 at 00:23
1

Wasn't that harsh. Asker's still alive after all. – user4581301 Jan 16 '21 at 00:47

What is the proper way of using cin.fail() for validating the input?

1 Answers1