/// <summary>
/// When got the focus, handle the lost focus event.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void OnMouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
{
if (!handleLostfocus && clb.ClientRectangle.Contains(clb.PointToClient(new System.Drawing.Point(e.X, e.Y))))
{
clb.LostFocus += new System.EventHandler(this.ValueChanged);
handleLostfocus = true;
}
}
