Question

I have an iphone application in which I want to check whether a string value is from 0 to 9. If it is like that, I want to do something else. Does anybody know how to do this?

Answer 1

if (string.length == 1 && [string characterAtIndex:0] >= '0' && [string characterAtIndex:0] <= '9') {
    // do something
}

This checks for the string being exactly 1 character long and that character being either 0, 1, 2, 3, 4, 5, 6, 7, 8 or 9.