title: Is InvokeRequired required?
body: <p>My coworker likes to do this</p>
  
  <pre><code>if (!listbox1.InvokeRequired)
      listbox1.Items.Add(Container.error_message);
  else
      listbox1.Invoke((MethodInvoker)delegate
      {
          listbox1.Items.Add(Container.error_message);
      });
  </code></pre>
  
  <p>Why do he have to check for InvokedRequired? Will it be better to just use this statement only?</p>
  
  <pre><code>    listbox1.Invoke((MethodInvoker)delegate
      {
          listbox1.Items.Add(Container.error_message);
      });
  </code></pre>