Sciter TIScript KeyEvent

function movable() // install movable window handler
{
    function onKeyDown(evt) {
        if(evt.keyCode == Event.VK_CONTROL )
        {
            is_ctrl = true;
        }
    }
    function onKeyUp(evt) {
        if(evt.keyCode == Event.VK_CONTROL )
        {
            is_ctrl = false;
        }
    }
    function onWheelPos(evt){
        alert(0);
    }
    view.root.subscribe(onKeyDown, Event.KEY, Event.KEY_DOWN );
    view.root.subscribe(onKeyUp, Event.KEY, Event.KEY_UP );
    view.root.subscribe(onWheelPos, Event.MOUSE, Event.MOUSE_WHEEL );
    return false;
}
movable();