Any object in the database can be erased with the following function:
Acad::ErrorStatus AcDbObject::erase( Adesk::Boolean Erasing = true);
By default, you cannot open an erased object with the acdbOpenObject() function. If you attempt to do so, the eWasErased error code will be returned.
extern Acad::ErrorStatus acdbOpenObject( AcDbObject*& obj, AcDbObjectId objId, AcDb::OpenMode openMode, Adesk::Boolean openErasedObject = Adesk::kFalse);
To open an erased object, use kTrue for the last parameter of the acdbOpenObject() function.
Container objects such as polylines and block table records usually provide the option of skipping erased elements when iterating over their contents. The default behavior is to skip erased elements.
Erased objects are not filed out to DWG or DXF files.