title: NSClassFromString returns nil
body: <p>Why does <code>NSClassFromString</code> return <code>nil</code> ? As per the definition it has to return class name.
  How should I take care to rectify this problem? I need to instantiate a class from string and call the method, which is in the class, using the instance created.</p>
  
  <p>This is how my code looks like:</p>
  
  <pre><code>id myclass = [[NSClassFromString(@"Class_from_String") alloc] init];
  [myclass method_from_class];
  </code></pre>
  
  <p>But the <code>method_from_class</code> function is not being called, control is not going into it. And my code is error free. Any idea how to solve this in Objective-C?</p>