title: NSJSONSerialization JSONObjectWithData returns null if json object has some junk value
body: <p>I am using following code snippet to parse JSON object from the url.</p>
  
  <pre><code>   NSData* data = [NSData dataWithContentsOfURL:[NSURL URLWithString:urlAddress] options:NSDataReadingUncached error:&amp;error];
      if (error != nil) {
          NSLog(@"%@",[error localizedDescription]);        
      }   else {
          NSLog(@"No Error: %@", data);  //looks good here. console displays the raw data 
      }
  
      id result = [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:&amp;error];
  
      if (error != nil) {
          NSLog(@"%@",[error localizedDescription]);
          return nil;
  
      }   else {
          NSLog(@"No Error: %@", [result objectForKey:@"exams"]); //console displays the value ("No Error: value for key...") unless a degree symbol is present in which case it displays No Error: (null)
  
      }
  </code></pre>
  
  <p>I have some 10 urlAddresses,for 7 urls JSONObjectWithData returns json object.for remaining 3 urls  JSONObjectWithData returns null.I tried opening this urls in safari.I have seen some junk characters in it.I suspect problem is with this junk character.How to solve this issue?</p>
  
  <p>I have seen this "<a href="https://stackoverflow.com/questions/11349819/jsonobjectwithdata-returns-null-if-degree-symbol-is-in-json-object">JSONObjectWithData returns null if degree symbol is in json object</a>" link similar.suggested to use unicode escape sequence.How to use this  "unicode escape sequence" to solve my issue.</p>