AutoCAD .Net 不同文档间复制对象

使用Clone()函数可以在同一 AutoCAD 文档间复制对象。
在不同的 AutoCAD 文档间复制对象，则需要调用Database类的方法WblockCloneObjects。
以下代码演示，将一外部 AutoCAD 文档（D:\test.dwg）中的图元复制到当前文档。

[CommandMethod("TestCopyBetweenDwgFiles")]
public void TestCopyBetweenDwgFiles()
{
    Document doc = Application.DocumentManager.MdiActiveDocument;
    Database db = doc.Database;

    using (Transaction tr = db.TransactionManager.StartTransaction())
    {
        using (Database srcDb = new Database(false, false))
        {
            srcDb.ReadDwgFile(@"D:\test.dwg", FileOpenMode.OpenForReadAndReadShare, true, "");
            ObjectIdCollection oids = GetDbModelSpaceEntities(srcDb);

            if (oids.Count > 0)
            {
                IdMapping idMap = new IdMapping();
                srcDb.WblockCloneObjects(oids, db.CurrentSpaceId, idMap, DuplicateRecordCloning.Ignore, false);
            }
        }

        tr.Commit();
    }
}

/// <summary>
/// 获取数据库模型空间的所有图元
/// </summary>
private ObjectIdCollection GetDbModelSpaceEntities(Database db)
{
    ObjectIdCollection oids = new ObjectIdCollection();

    using (Transaction tr = db.TransactionManager.StartTransaction())
    {
        BlockTable blockTbl = tr.GetObject(db.BlockTableId, OpenMode.ForRead) as BlockTable;
        BlockTableRecord modelSpace = tr.GetObject(
            blockTbl[BlockTableRecord.ModelSpace],
            OpenMode.ForRead) as BlockTableRecord;

        foreach (ObjectId oid in modelSpace)
        {
            DBObject dbobj = tr.GetObject(oid, OpenMode.ForRead);
            if (dbobj is Entity)
            {
                oids.Add(oid);
            }
        }
    }

    return oids;
}