private List <MediaData> GetMediaDataListForSection(SectionNode sNode) { List <MediaData> mediaList = new List <MediaData> (); sNode.AcceptDepthFirst( delegate(urakawa.core.TreeNode n) { if (n != null && n is PhraseNode && ((PhraseNode)n).Audio != null) { mediaList.Add(((PhraseNode)n).Audio.MediaData); } return(true); }, delegate(urakawa.core.TreeNode n) { }); return(mediaList); }