var prevent=false; if(e.ctrlKey){ if(e.keyCode==90){ //ctrl+z self.undo(); prevent = true; }else if(e.keyCode==89){ //ctrl+y self.redo(); prevent = true; } } if(e.keyCode==46 || e.keyCode==8){ //delete or backspace self._delete(self.selected); prevent = true; } if(prevent){ dojo.stopEvent(e); }