title: Easiest way to make ToolStripMenuItem.Selected = true
body: <p>I have a <code>ToolStripMenuItem</code> named <code>mailResultsToolStripMenuItem</code>. Now I want it to be <code>.Selected = true</code> when users click on it and <code>.Selected = false</code> when users click it again. I tried:</p>
  
  <pre><code>mailResultsToolStripMenuItem.Selected = true;
  </code></pre>
  
  <p>but it shows an error that the property is <em>read-only</em>.</p>