public void Close(ElementEvent e) { DivElement menu = Document.GetElementById <DivElement>("histogram"); DivElement closeBtn = Document.GetElementById <DivElement>("histogramClose"); menu.Style.Display = "none"; Window.RemoveEventListener("click", Close, true); ImageElement image = Document.GetElementById <ImageElement>("graph"); image.RemoveEventListener("mousedown", MouseDown, false); image.RemoveEventListener("mousemove", mousemove, false); image.RemoveEventListener("mouseup", mouseup, false); dropDown.RemoveEventListener("change", CurveStyleSelected, false); dropDown.RemoveEventListener("click", IgnoreMe, true); }