Validation for Number with character limit

- (BOOL)NumberValidation:(NSString *)string  {

    NSUInteger newLength = [string length];

    NSCharacterSet *cs = [[NSCharacterSet characterSetWithCharactersInString:@"1234567890"] invertedSet];

    NSString *filtered = [[string componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@""];

    return (([string isEqualToString:filtered])&&(newLength <= 3));

}

in your button action event just use this like bellow...

-(IBAction)ButtonPress{

    

    if ([self NumberValidation:yourString]) {

        NSLog(@"Macth here");

    }

    else {

        NSLog(@"Not Match here");

    }

}

http://stackoverflow.com/questions/9477563/how-to-enter-numbers-only-in-uitextfield-and-limit-maximum-length