Objective-C: Imitation of C# "String.Contains()" method

The method returns a YES or a NO:

Method signature:

- (BOOL) containsString:(NSString *) string
                options:(NSStringCompareOptions) options;

Method body:

- (BOOL) containsString:(NSString *) string
                options:(NSStringCompareOptions) options {
    NSRange rng = [self rangeOfString:string options:options];
    return rng.location != NSNotFound;
}

If NSStringCompareOptions make no difference, a 0 can be passed to the method.