Playlists and the PlaylistCollection Object
[The feature associated with this page, Windows Media Player SDK, is a legacy feature. It has been superseded by MediaPlayer. MediaPlayer has been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer instead of Windows Media Player SDK, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]
The PlaylistCollection object gives you access to playlists in the library and has methods for creating new, empty playlists and new playlists from metafiles.
Working with Existing Playlists
The PlaylistCollection.getAll and PlaylistCollection.getByName methods each return a PlaylistArray object, which can contain multiple playlists.
The PlaylistCollection.getAll method returns all of the existing playlists that are in the library. For example, you can call this method and then retrieve the playlists in the PlaylistArray object to determine whether a given playlist name has already been used, or to display all of the playlists to the user. The sample code in Playlist Attributes uses the getAll method.
The PlaylistCollection.getByName method returns all of the playlists with a given name. You can use this method to handle each of those playlists separately.
You can also use the getByName method to retrieve a unique playlist by name. In that case, the PlaylistArray object has only one element. The following C# example demonstrates this technique.
IWMPPlaylistArray PlayListArray;
IWMPPlaylist Playlist;
// Store the playlist named "BluesTest" in the array
PlayListArray = Player.playlistCollection.getByName("BluesTest");
// Retrieve the first playlist in the collection.
Playlist = PlaylistArray.Item(0);
Working with New Playlists
You can use the PlaylistCollection.newPlaylist method to create a new, empty playlist. The method returns a reference to the new Playlist object. You can then call the Playlist.appendItem method to add media items to the playlist.
You can also create a new playlist based on a playlist metafile. First, pass the name of the playlist and the path to the metafile to the Player.newPlaylist method. That method returns a reference to the new Playlist object. Then, pass the new Playlist object to the PlaylistCollection.importPlaylist method to add it to the library.
Notice the difference between the PlaylistCollection.newPlaylist method and the Player.newPlaylist method. The PlaylistCollection method creates a new, empty playlist and adds it to the library. The Player method creates a new, populated Playlist object but does not add it to the library.
Throughout this topic, the Player object was defined in the following manner:
AxWMPLib.AxWindowsMediaPlayer Player;
using WMPLib;
The following C# example demonstrates importing a playlist from a metafile. The strPListName argument specifies the name of the new playlist. The strMetaFileName specifies the name of the metafile from which the playlist is imported.
private IWMPPlaylist importPlaylist(string strPlaylistName, string strMetaFileName)
{
IWMPPlaylist NewPlaylist;
IWMPPlaylist ImportPlaylist;
NewPlaylist = Player.newPlaylist(strPlaylistName, strMetaFileName);
ImportPlaylist = Player.playlistCollection.importPlaylist(NewPlaylist);
return ImportPlaylist;
}
Related topics