title: Check if Keys is Letter/Digit/Special Symbol
body: <p>I override <code>ProcessCmdKey</code> and when I get <code>Keys</code> argument, I want to check if this <code>Keys</code> is Letter or Digit or Special Symbol.</p>
  
  <p>I have this snippet</p>
  
  <pre><code>    protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
      {
              char key = (char)keyData;
              if(char.IsLetterOrDigit(key)
              {
                  Console.WriteLine(key);
              }
              return base.ProcessCmdKey(ref msg, keyData);
      }
  </code></pre>
  
  <p>Everything works for letters and digits. but when I press F1-F12 it converts them to letters.</p>
  
  <p>Maybe someone knows better way to solve this task?</p>