Comparing Value of Int to String

Say for example you have a menu set up, and you have a limited amount of choices. And you only want to allow ..say 1-4 and cancel out all other options. Like you have an error message come up if they hit anything other than 1-4. Anyway to do that. I went through the forum search and found a few things sorta like I'm asking, but I'm new to c++ and could exactly relate it enough for use.

Like I enter the highed ascii character in int value

dec value 5 to 122 in ascii chart being alittle z.
anyway to directly error out the keys themselves?

Or how else would you go about it?

Thanks

can someone please put this in c++ board, I by mistake put it in the c board. pretty please. thanks.

Aw, you're no fun. I was going to roll out the clever scanf scanset solution:

Code:

---

#include <stdio.h>

void discard(FILE *in);

int main(void)
{
  char option;

  printf("1) One\n2) Two\n3) Three\n4) Four\n> ");
  fflush(stdout);
  while (scanf("%[1234]", &option) != 1) {
    fprintf(stderr, "Invalid option, try again\n> ");
    clearerr(stdin);
    discard(stdin);
  }

  return 0;
}

void discard(FILE *in)
{
  int ch;

  while ((ch = fgetc(in)) != EOF && ch != '\n')
    ;
}

---

;)

But here's a potential C++ solution as well, since this thread will probably be moved:

Code:

---

#include <iostream>

using namespace std;

int main()
{
  int option;

  cout<<"1) One\n2) Two\n3) Three\n4) Four\n> ";
  while (!(cin>> option) || option < 1 || option > 4) {
    cerr<<"Invalid option, try again\n> ";
    cin.clear();
    cin.ignore(cin.rdbuf()->in_avail(), '\n');
  }
}

---

hey thanks for the quick reply heh even before it was moved heh.

Code:

---

#include <stdio.h>

---

or you could just change this to

Code:

---

#include <csdtio>
using namespace std;

---

And have the C solution work in C++.

>And have the C solution work in C++.
And then get run off of the C++ forum because you used scanf. Purists are annoying, aren't they? ;)

By the way, it's <cstdio>. Case is important, but spelling is too. :D

Why yes... purists are annoying... ;)