MxDrawResbuf param = new MxDrawResbuf();
        param.AddObjectId(id);

        MxDrawResbuf ret = (MxDrawResbuf)axMxDrawX1.CallEx("Mx_IsErased", param);
        if(ret.AtString(0) == "Ok")
        {

            MessageBox.Show("对象被删除");
        }

            MxDrawResbuf param = new MxDrawResbuf();
            param.AddObjectId(ent.ObjectID);
    
            MxDrawApplication app = new MxDrawApplication();
            MxDrawResbuf ret = (MxDrawResbuf)app.CallEx("Mx_IsErased", param);
            if (ret.AtString(0) == "Ok")
            {

                MessageBox.Show("对象被删除");
            }
            else 
            {
                MessageBox.Show("对象没有被删除");
            }