// 得到数据库对象
         MxDrawDatabase database = (MxDrawDatabase)(axMxDrawX1.GetDatabase());

         // 得到当前的标注样式对象.
         MxDrawDimStyleTableRecord curDimRecord = database.GetDimStyleTable().GetAt(database.CurrentlyDimstyleName, false);

         if (curDimRecord != null)
         {
             // 设置标注对象的全局缩放比例
             // 40,在m_dimscale值的DXF代码
             // 20.0 是新的全局缩放比例
             curDimRecord.SetDimVarDouble(40, 20.0);
         }