AutoCAD.net: 如何实现裁剪功能--Trim

public void TrimMap(Polyline cutBox){    //关闭对象捕捉功能避免误删除    Application.SetSystemVariable("SNAPMODE", 0);    Application.SetSystemVariable("MODEMACRO", "正在修剪");    //获取最小与最大点    Point3d minPoint = cutBox.GeometricExtents.MinPoint;    Point3d maxPoint = cutBox.GeometricExtents.MaxPoint;    //设置缩放视口    Tools.RunCommand("Zoom", "W", new Point3d(minPoint.X - 10, minPoint.Y - 10, 0), new Point3d(maxPoint.X + 10, maxPoint.Y + 10, 0));    //裁剪精度    Polyline offsetBox = cutBox.GetOffsetCurves(0.2)[0] as Polyline;    if (offsetBox.Area < cutBox.Area)    {        offsetBox = cutBox.GetOffsetCurves(-0.2)[0] as Polyline;    }    //裁剪    for (int i = 0; i < offsetBox.NumberOfVertices; i++)    {        Point3d p1 = offsetBox.GetPoint3dAt(i);        Point3d p2 = new Point3d();        if (i == offsetBox.NumberOfVertices - 1)        {            p2 = offsetBox.GetPoint3dAt(0);        }        else        {            p2 = offsetBox.GetPoint3dAt(i + 1);        }        Tools.RunCommand("TRIM", cutBox.ObjectId, "", "F", p1, p2, "", "");    }    offsetBox.Dispose();    Application.SetSystemVariable("MODEMACRO", "修剪完成");}