大型的CAD文件中图层过多时会导致其浏览速度和各种操作变慢,本程序可以方便的清理CAD文件中的层,将不同层中的对象进行归并,以加速操作速度.-Large-scale CAD file layer will lead to excessive speed of their browser and slow down operation, the procedure can easily clean up CAD file layer, different layers of objects mer