title: listener c# like java
body: <p>I have field string in struct, 
  and i want learn real-time changed this field.</p>
  
  <pre><code>struct example {
  public string ex;
  }
  
  examp = new example();&lt;BR&gt;
  examp.ex = "test";
  
  ////// then program work and eamp.ex = "bing";
  </code></pre>
  
  <p>I need method </p>
  
  <pre><code>on_ex_changed() 
  {
      if examp.ex changed then ..... 
  }
  </code></pre>
  
  <p>online and simple plz</p>