title: Return Facebook profile picture
body: <p>Is that possible to retrieve the name of the picture file from the Facebook profile picture?</p>
  
  <p>What I want to do is this: When the user logs in I will retrieve the user's profile pic and then save it on a file. However, I want to always check whether the user updated the picture on Facebook and if yes save it on the file again.</p>
  
  <p>Is it possible to get the name of the file, and therefore I can compare them?</p>
  
  <p>Here is the code that I use to download the picture:</p>
  
  <pre><code>NSString *urlString = [NSString stringWithFormat:@"https://graph.facebook.com/%@/picture?width=100&amp;height=100",[[PFUser currentUser] objectForKey:@"fbId"]];                
      NSURL *url = [NSURL URLWithString:urlString];
      NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];
  
      AFHTTPRequestOperation *requestOperation = [[AFHTTPRequestOperation alloc] initWithRequest:urlRequest];
      requestOperation.responseSerializer = [AFImageResponseSerializer serializer];
  
      [requestOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject){
          profilePicture = [UIImage imageWithData: operation.responseData];
          NSDictionary&lt;FBGraphUser&gt; *me = (NSDictionary&lt;FBGraphUser&gt; *)responseObject;
          NSLog(@"ResponseObject %@", me.username);
          NSLog(@"Profile Image %@",profilePicture);
          [self saveImageOnDisk:profilePicture];
  }];
  </code></pre>