?
Solved

atoi or what?

Posted on 1998-08-06
4
Medium Priority
?
495 Views
Last Modified: 2010-04-02
Ok, the problem that Im having is that Iam simplly trying to add a failsafe into my code which is already written!
The code accepts an integer input but what if the user presses a character key (accidently of course). I have tried using 'int =  atoi(char)' which works great but if I do press a character key then a zero is placed in the input! Does anybody have a suggestion that might resolve this problem?

Thanks for any help,

bbarnette
0
Comment
Question by:bbarnette
  • 2
4 Comments
 
LVL 8

Expert Comment

by:trestan
ID: 1169547
Use isalpha to check whether your input is a char.
0
 
LVL 8

Expert Comment

by:trestan
ID: 1169548
Pls refer to the online help for the group of Character Classification routines, which tests a specified single-byte character, wide character, or multibyte character for satisfaction of a condition.
By the way, you have post a duplicate question.
0
 

Author Comment

by:bbarnette
ID: 1169549
I have tried isalpha and that did not solve it either
0
 
LVL 2

Accepted Solution

by:
mlev earned 200 total points
ID: 1169550
if (sscanf(string, "%d", &integer) != 1) {
  /* bad input */
}

But this still allows for nondigits at the end.

This doesn't:
if (strspn(string, "-0123456789") != strlen(string)) {
  /* bad input */
} else {
  integer = atoi(string);
}

Or this:
int i;
for (i = 0; isdigit(string[i]) || string[i] == '-'; i++);
if (string[i] != '\0') {
  /* bad input */
} else {
  integer = atoi(string);
}
0

Featured Post

VIDEO: THE CONCERTO CLOUD FOR HEALTHCARE

Modern healthcare requires a modern cloud. View this brief video to understand how the Concerto Cloud for Healthcare can help your organization.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

  Included as part of the C++ Standard Template Library (STL) is a collection of generic containers. Each of these containers serves a different purpose and has different pros and cons. It is often difficult to decide which container to use and …
Basic understanding on "OO- Object Orientation" is needed for designing a logical solution to solve a problem. Basic OOAD is a prerequisite for a coder to ensure that they follow the basic design of OO. This would help developers to understand the b…
The viewer will learn additional member functions of the vector class. Specifically, the capacity and swap member functions will be introduced.
The viewer will be introduced to the technique of using vectors in C++. The video will cover how to define a vector, store values in the vector and retrieve data from the values stored in the vector.
Suggested Courses

579 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question