Object ARX 根据点选择其内包含的要素
在AutoCAD二次开发的过程中,随时可能会遇到框选要素的情况.
为了将我入门时的学习过程记录下来,特此撰写.

AcDbPolyline * pPline;struct resbuf* pointlist;pointlist = acutNewRb(RT3DPOINT);//ads_point pt;int numVerts = pPline->numVerts();//矩形的点顺序for (int i=0; i<numVerts; i++){AcGePoint3d tempLineSeg3d;pPline->getPointAt(i,tempLineSeg3d);ads_point pt;pt[X] = tempLineSeg3d.x;pt[Y] = tempLineSeg3d.y;pt[Z] = tempLineSeg3d.z;if(0 == i){pointlist = acutBuildList(RT3DPOINT,pt,NULL);}else{pointlist= acutBuildList(RTRESBUF, pointlist,RT3DPOINT, pt, NULL);}}// 选择图框内的要素ads_name ss;acedSSGet(_T("WP"),pointlist,NULL,NULL,ss);long lSSLen=0;if(RTNORM != acedSSLength(ss, &lSSLen) || lSSLen<=0 ){// acutPrintf(_T("\n面积线层上没有任何实体!\n"));return FALSE;}