title: NSString is integer?
body: <p>How to check if the content of a NSString is an integer value? Is there any readily available way?</p>
  
  <p>There got to be some better way then doing something like this:</p>
  
  <pre><code>- (BOOL)isInteger:(NSString *)toCheck {
    if([toCheck intValue] != 0) {
      return true;
    } else if([toCheck isEqualToString:@"0"]) {
      return true;
    } else {
      return false;
    }
  }
  </code></pre>