Playlist.attributeCount

發行項
4/26/2023

[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 It has been superseded by MediaPlayer.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 attributeCount property retrieves the number of attributes associated with the playlist.

Syntax

player.currentPlaylist.attributeCount

Possible Values

This property is a read-only Number (long).

Remarks

Because playlists can come from many different sources, they can have several different sets of properties. This method retrieves the total number of properties available so that the other methods of the Playlist object can access them.

To retrieve the value of this property, read access to the library is required. For more information, see Library Access.

For information about the attributes supported by Windows Media Player, see the Windows Media Player Attribute Reference.

Examples

The following JScript example illustrates how various properties and methods of the Playlist and Media objects are used.

function onLoad() {
    var display;
    var pl = player.currentPlaylist;

    pl.setItemInfo("custom playlist attribute", "changed");
    pl.item(0).setItemInfo("new custom attribute", "5");

    display = pl.attributeCount + " Playlist Attributes:\r\r";

    for (var i = 0; i < pl.attributeCount; ++i) {
        display = display + pl.attributeName(i) + ": ";
        display = display + pl.getItemInfo(pl.attributeName(i)) + "\r";
    }

    for (var j = 0; j < pl.count; ++j) {
        display = display + "\rTrack " + j + "\r"
        display = display + pl.item(j).attributeCount + " Attributes:\r\r";

        for (var k = 0; k < pl.item(j).attributeCount; ++k) {
            var it = pl.item(j);  // Media object
            display = display + it.getAttributeName(k) + ": ";
            display = display + it.getItemInfo(it.getAttributeName(k)) + "\r";
        }
    }

    myText.value = display;
}

Requirements

Requirement	Value
Version	Windows Media Player version 7.0 or later.
DLL	Wmp.dll

共用方式為