static CheckBox()
{
Type type = typeof(CheckBox);
DefaultStyleKeyProperty.OverrideMetadata(type, new FrameworkPropertyMetadata(type));
ContextMenuService.Attach(type);
ToolTipService.Attach(type);
StyleProperty.OverrideMetadata(typeof(CheckBox), new FrameworkPropertyMetadata(null, new CoerceValueCallback(OnCoerceStyle)));
}