title: Get Index of Control in an Control-Array
body: <p>I have a TextBox Array</p>
  
  <pre><code>private TextBox[,] Fields = new TextBox[9, 9];
  </code></pre>
  
  <p>and all the TextBoxes have got the same TextChanged-Event</p>
  
  <pre><code>void Field_Changed( object sender, EventArgs e )
  </code></pre>
  
  <p>Is there a way to get the Index of the sender in the Array (without giving each TextBox it's own EventHandler)?</p>