title: Get a char from NSString and convert to int
body: <p>In C# I can convert any char from my string to integer in the following manner</p>
  
  <pre><code>intS="123123";
  int i = 3;
  Convert.ToInt32( intS[i].ToString());
  </code></pre>
  
  <p>What is the shortest equivalent of this code in Objective-C ?</p>
  
  <p>The shortest one line code I've seen is </p>
  
  <pre><code>[NSNumber numberWithChar:[intS characterAtIndex:(i)]]
  </code></pre>