我是javascript的绝对新手，但我只是想调整JPlayer使用XML文件作为播放列表而不是硬编码的播放列表。所以，这是创建播放列表的代码：
//<![CDATA[
$(document).ready(function(){
var Playlist = function(instance, playlist, options) {
var self = this;
this.instance = instance; // String: To associate specific HTML with this playlist
this.playlist = playlist; // Array of Objects: The playlist
this.options = options; // Object: The jPlayer constructor options for this playlist
this.current = 0;
this.cssId = {
jPlayer: "jquery_jplayer_",
interface: "jp_interface_",
playlist: "jp_playlist_"
};
this.cssSelector = {};
$.each(this.cssId, function(entity, id) {
self.cssSelector[entity] = "#" + id + self.instance;
});
if(!this.options.cssSelectorAncestor) {
this.options.cssSelectorAncestor = this.cssSelector.interface;
}
$(this.cssSelector.jPlayer).jPlayer(this.options);
$(this.cssSelector.interface + " .jp-previous").click(function() {
self.playlistPrev();
$(this).blur();
return false;
});
$(this.cssSelector.interface + " .jp-next").click(function() {
self.playlistNext();
$(this).blur();
return false;
});
};
Playlist.prototype = {
displayPlaylist: function() {
var self = this;
$(this.cssSelector.playlist + " ul").empty();
for (i=0; i < this.playlist.length; i++) {
var listItem = (i === this.playlist.length-1) ? "<li class='jp-playlist-last'>" : "<li>";
listItem += "<a href='#' id='" + this.cssId.playlist + this.instance + "_item_" + i +"' tabindex='1'>"+ this.playlist[i].name +"</a>";
// Create links to free media
if(this.playlist[i].free) {
var first = true;
listItem += "<div class='jp-free-media'>(";
$.each(this.playlist[i], function(property,value) {
if($.jPlayer.prototype.format[property]) { // Check property is a media format.
if(first) {
first = false;
} else {
listItem += " | ";
}
listItem += "<a id='" + self.cssId.playlist + self.instance + "_item_" + i + "_" + property + "' href='" + value + "' tabindex='1'>" + property + "</a>";
}
});
listItem += ")</span>";
}
listItem += "</li>";
// Associate playlist items with their media
$(this.cssSelector.playlist + " ul").append(listItem);
$(this.cssSelector.playlist + "_item_" + i).data("index", i).click(function() {
var index = $(this).data("index");
if(self.current !== index) {
self.playlistChange(index);
} else {
$(self.cssSelector.jPlayer).jPlayer("play");
}
$(this).blur();
return false;
});
// Disable free media links to force access via right click
if(this.playlist[i].free) {
$.each(this.playlist[i], function(property,value) {
if($.jPlayer.prototype.format[property]) { // Check property is a media format.
$(self.cssSelector.playlist + "_item_" + i + "_" + property).data("index", i).click(function() {
var index = $(this).data("index");
$(self.cssSelector.playlist + "_item_" + index).click();
$(this).blur();
return false;
});
}
});
}
}
},
playlistInit: function(autoplay) {
if(autoplay) {
this.playlistChange(this.current);
} else {
this.playlistConfig(this.current);
}
},
playlistConfig: function(index) {
$(this.cssSelector.playlist + "_item_" + this.current).removeClass("jp-playlist-current").parent().removeClass("jp-playlist-current");
$(this.cssSelector.playlist + "_item_" + index).addClass("jp-playlist-current").parent().addClass("jp-playlist-current");
this.current = index;
$(this.cssSelector.jPlayer).jPlayer("setMedia", this.playlist[this.current]);
},
playlistChange: function(index) {
this.playlistConfig(index);
$(this.cssSelector.jPlayer).jPlayer("play");
},
playlistNext: function() {
var index = (this.current + 1 < this.playlist.length) ? this.current + 1 : 0;
this.playlistChange(index);
},
playlistPrev: function() {
var index = (this.current - 1 >= 0) ? this.current - 1 : this.playlist.length - 1;
this.playlistChange(index);
}
};
var mediaPlaylist = new Playlist("1", [
{
name:"song1",
mp3: "song1.mp3",
poster: "http://www.jplayer.org/video/poster/Incredibles_Teaser_640x272.png"
},
{
name:"song2",
mp3: "song2.mp3",
poster: "http://www.jplayer.org/video/poster/Incredibles_Teaser_640x272.png"
},
{
name:"song3",
mp3: "song3.mp3",
poster: "http://www.jplayer.org/video/poster/Incredibles_Teaser_640x272.png"**
}
], {
ready: function() {
mediaPlaylist.displayPlaylist();
mediaPlaylist.playlistInit(false); // Parameter is a boolean for autoplay.
},
ended: function() {
mediaPlaylist.playlistNext();
},
swfPath: "js",
supplied: "ogv, m4v, oga, mp3"
});
});
以“var mediaPlaylist”开头的部分是我需要更改的唯一部分。我没有将键/值作为名称：songname，mp3：mp3等，我希望它从XML文件中提取这些值，或者更好的是，只需将它们从XML中推送到数组中即可：
<song>songname</song>
<mp3>file.mp3</mp3>
这里让我感到困惑的是这个函数/数组是如何设置的......太多的花括号和括号来包裹我的脑袋。如何在不破坏它的情况下进入此阶段？
答案 0 :(得分：1)
如果您有以下格式的服务器端XML播放列表文件：
<?xml version="1.0" encoding="UTF-8"?>
<playlist>
<entry>
<song>songname</song>
<mp3>file.mp3</mp3>
</entry>
<entry>
<song>songname2</song>
<mp3>file2.mp3</mp3>
</entry>
</playlist>
然后您可以通过AJAX从客户端加载它，并从XML创建一个JSON数组。以下示例使用jQuery JavaScript框架以及jquery-json plugin（仅将数组格式化为JSON）。你应该可以在Chrome或Firefox上运行它，因为它们都有console（通过在浏览器中按 F12 访问），我在其中输出JSON数组。
注意：如果您不使用其中任何一种浏览器，则可以将console.log(...)更改为alert(...)。
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Title</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.min.js"></script>
<script type="text/javascript" src="http://jquery-json.googlecode.com/files/jquery.json-2.2.min.js"></script>
<script type="text/javascript">
$(function() {
var Playlist = function(instance, playlist, options) {
var self = this;
this.instance = instance;
this.playlist = playlist;
this.options = options;
};
function getPlaylist(callback) {
var songs = new Array();
$.ajax({
dataType:'xml',
url:'songs.xml',
success : function (xml) {
$(xml).find('entry').each(function() {
songs.push({name: $(this).find('song').text(), mp3: $(this).find('mp3').text()});
});
callback(songs);
}
});
}
getPlaylist(function(songs) {
var playlistFromXML = jQuery.toJSON(songs);
var mediaPlaylist = new Playlist('1', playlistFromXML, null);
console.log(mediaPlaylist);
// etc...
});
});
</script>
</head><body></body></html>
归功于How to return an array from jQuery ajax success function properly?回答，因为我使用该方法从jQuery $.ajax success方法返回值。
您必须将var mediaPlaylist = new Playlist()构造函数重构为回调函数，因为您无法从回调中返回播放列表值（请参阅How can I catch the return value from the result() callback function that I'm using?）
希望这会有所帮助： - ）