how to modify vertex of AcDb3dPolyline which is not in database

[475867377]

the pPolying is AcDb3dPolyline which is not in database.i want to modify its vertex like the follow picture,but it failed,return eNoDatabase error.i want to know how to modify the vertex.

[tbrammer · Accepted solution]

Your are using the iterator wrong. Try this:

	AcDbObjectIterator *it = pPolying->vertexIterator();
	if (it)  {
		for (it->start(); !it->done(); it->step())	{
			AcDb3dPolylineVertex* pVertex = AcDb3dPolylineVertex::cast(it->entity());
			if (pVertex)
				es = pVertex->setPosition(pt);
				// Don't delete pVertex!
		}
		delete it; // But delete the iterator when you are done with it
	}