title: C# Get dictionary key by value where value is of struct type
body: <p>please tell me is this possible to do and how to get this.</p>
  
  <pre><code>In C# I have a struct like:
  
  public struct FrmData{
  int num;
  int x;
  Timer t;
  }
  </code></pre>
  
  <p>I use than dictionary where value is that structure.</p>
  
  <pre><code>public Dictionary&lt;int, FrmData&gt; dictionary;
  </code></pre>
  
  <p>when my Timer t elapsed, he raises event </p>
  
  <pre><code>public void eventHandlerTick(object sender, EventArgs e){
  switch(key){case 1:break;}
  }
  </code></pre>
  
  <p>my question is: can I somehow to get key of my dictionary from this timer which is raised this event ?!
  thank you</p>