if(this._scrollBarWidth){ return this._scrollBarWidth; } this._scrollBarWidth = 18; try{ var e = document.createElement("div"); e.style.cssText = "top:0;left:0;width:100px;height:100px;overflow:scroll;position:absolute;visibility:hidden;"; document.body.appendChild(e); this._scrollBarWidth = e.offsetWidth - e.clientWidth; document.body.removeChild(e); delete e; }catch (ex){} return this._scrollBarWidth;