title: Prevent ToolStripDropDownButton from being closed as long as no item is clicked
body: <p>How can I prevent a ToolStripDropDownButton from being closed until a item or the arrow that opens the menu is clicked?</p>
  
  <p>A standart .net Winforms ToolStripDropDownButton holds its menu just as long open as you hover the menu with the mouse...</p>
  
  <p>I thought of catching it in the closing event and then say e.Cancel = false but unfortunately it seems like ToolStripDropDownButton has no closing event just the ToolStripDropDown</p>