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Playlists and Media Items

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[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 It has been superseded by MediaPlayer.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.]

A playlist is a set of media items. A Playlist object can manipulate the Media objects that represent those items.

Retrieving Media Items

For an existing playlist, you can read the Playlist.count property to determine how many media items are in the playlist, and you can get a reference to the Media object corresponding to a specific item using the Playlist.item property.

The following C# example retrieves an object reference to a specific media item. (Throughout this topic, the variable pList is a reference to a Playlist object.)

currMedia = pList.Item(0);

The following C# example retrieves the names of all the media items in a playlist and puts them in a ListBox named lstOutput.

for (j=0; j < pList.count; j++)
{
    strItemName = pList.get_Item(j).name;
    lstOutput.Items.Add(strItemName);
}

Adding Items to a Playlist

You can add a media item to the end of a playlist or at a specific position in a playlist, using the Playlist.appendItem and Playlist.insertItem methods.

Throughout this topic, the Player object was defined in the following manner:

AxWMPLib.AxWindowsMediaPlayer Player;
using WMPLib;

The following C# example demonstrates both techniques by adding the current media item to a playlist named "BluesTest", first at the end and then at the beginning of the playlist.

IWMPPlaylistCollection pListColl;
IWMPPlaylistArray pListArray;
IWMPPlaylist pList;

// Initialize the Media object
IWMPMedia currMedia = Player.currentMedia;

if(currMedia != null)
{
    // Retrieve the playlist collection
    pListColl = Player.playlistCollection;

    // Retrieve a playlist array containing
    // playlists named BluesTest
    pListArray = pListColl.getByName("BluesTest");

    // Retrieve the first element with this name from the
    // array.
    pList = pListArray.Item(0);

    // Add the current item to the end, and then, the beginning
    // of the specified playlist.
    pList.appendItem(currMedia);
    pList.insertItem(0, currMedia);
}

When you create a new, empty playlist by using the PlaylistCollection.newPlaylist method, you can add media items to it by repeatedly calling the Playlist.appendItem method.

Manipulating Media Items in a Playlist

You can change the position of a media item in the playlist by using the Playlist.moveItem method. You specify the item by its current index, and then you specify the new index. The following C# example moves an item from index 5 to index 0 within a playlist.

// Move the 6th item to the beginning
// of the specified playlist.
pList.moveItem(5, 0);

You can remove a media item from the playlist by using the Playlist.removeItem method. Note that if the removed item was not the final item in the playlist, the index values of the subsequent items change. The following C# example removes the specified item.

// Remove the currently playing item from the
// specified playlist.
pList.removeItem(currMedia);

Note

Users can change the contents of a playlist outside of your application. Whenever you manipulate the items in a playlist, you should monitor and handle the playlist-related events of the Windows Media Player control to ensure that your code works correctly. These events are Player.CurrentPlaylistChange and Player.PlaylistChange.

 

Managing Playlists

Media Object

Playlist Object