title: How to detect Help button press in Windows Forms MessageBox?
body: <p>I have a message box with 3 buttons: Yes, No, Help:</p>
  
  <pre><code>var result = MessageBox.Show("text", "title",
                  MessageBoxButtons.YesNo,
                  MessageBoxIcon.Warning,
                  MessageBoxDefaultButton.Button1,
                  true);
  </code></pre>
  
  <p>I can detect if Yes/No buttons where clicked something like this:</p>
  
  <pre><code>if(result == DialogResult.Yes)
      // some actions
  </code></pre>
  
  <p>How I can detect that Help button was pressed and execute my own code?</p>