title: Detect doubleClick on mdiContainer without a child (c# winforms)
body: <p>I've got a <code>Form</code> which is a <code>mdiContainer</code>. When the Form hasn't got a child, I want to capture the doubleClick event when a user doubleClicks the clientArea (same behavior as Photoshop). </p>
  
  <p>But when I set the <code>doubleClick</code> event, nothing happens.
  How can I achieve this?</p>