Checking is Silverlight is installed

function hasSilverlight() {
    try {
        try {
            // IE
            var AgControl = new ActiveXObject('AgControl.AgControl');

            return (true);
        }
        catch (e) {
            // Others
            if (navigator.plugins["Silverlight Plug-In"]) {
                return(true);
            }
        }
    }
    catch (e) {
        return (false);
    }
}

var el = document.getElementById("button_id");
el.parentNode.removeChild(el);