title: How to unbox from object to type it contains, not knowing that type at compile time?
body: <p>At the run-time I get boxed instance of some type. How to unbox it to underlying type?</p>
  
  <pre><code>Object obj;
  String variable = "Some text";
  
  obj = variable // boxing;
  
  // explicit unboxing, because we know the type of variable at compile time.
  
  var x = (String)obj     
  
  // Now let's pretend that we don't know the type of underlying object at compile time. 
  
  Type desiredType = obj.GetType(); // But we can figure out.
  
  //And now the question. 
  //How to express something like this:
  
  var y = (desiredType)obj; //Need to get unboxed instance of initial variable here; 
  </code></pre>