title: Detect if cursor is within the bounds of a control
body: <p>I have a user control</p>
  
  <pre><code>public partial class UserControl1 : UserControl, IMessageFilter
  {
      public UserControl1()
      {
          InitializeComponent();
          Application.AddMessageFilter(this);
      }
  
      public bool PreFilterMessage(ref Message m)
      {
          var mouseLocation = Cursor.Position;
  
          if (Bounds.Contains(PointToClient(mouseLocation)))
          {
              bool aBool = true;//breakpoint
              bool two = aBool;//just assignment so compiler doesn't optimize my bool out
          }
          if (m.Msg != 0x20a) // Scrolling Message
          {
              return false;//ignore message
          }
          return false;
      }
  }
  </code></pre>
  
  <p>When I float over the user control contained in a parent form, the breakpoint is not hit.  The breakpoint is hit in close proximity, but I can be in an actual textbox inside the user control and not get a hit.  How can I accurately determine if I am within the bounds of this user control?</p>
  
  <p>FWIW, I have two monitors.  It does not appear to make a difference which monitor I am using.</p>