Check whether an NSString contains a special character and a digit

Question

I need to check whether a string contains one uppercase letter, one lower case letter, one integer and one special character. How do I check?

Answer 1

Without any additional frameworks:

NSCharacterSet * set = [[NSCharacterSet characterSetWithCharactersInString:@"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"] invertedSet];

if ([aString rangeOfCharacterFromSet:set].location != NSNotFound) {
    NSLog(@"This string contains illegal characters.");
}

You could also use a regex (this syntax is from RegexKitLite: http://regexkit.sourceforge.net):

if ([aString isMatchedByRegex:@"[^a-zA-Z0-9]"]) {
    NSLog(@"This string contains illegal characters.");
}