通过某些RSS源获取XML时出现问题

我正在通过一些RSS提要获取XML。 我无法像“channel->description”那样对项目进行深度排序

NSString *resultValue=[[responseDictionary valueForKeyPath:@"rss.channel.description"] textContent];

以上结果:YouTube RSS订阅源

我的问题是如何解析……项目->说明…即(Andrews\U00A9 1982 MJJ Productions Inc.的音乐视频) 我得到 nil 如果我拿来像 valueForKeyPath:@"rss.channel.item.description"]

Key: rss Value: {
    "_text" = "\n";
    channel =     {
        "_text" = "\n";
        description =         {
            "_text" = "YouTube RSS Feed";
        };
        item =         (
                        {
                "_text" = "\n\t";
                description =                 {
                    "_text" = "Music video by Andrews \U00a9 1982 MJJ Productions Inc.";
                };
                enclosure =                 {
                    length = 294;
                    type = "application/x-shockwave-flash";
                    url = "http://youtube.com/v/Zi_XLOBDo_Y.swf";
                };
                link =                 {
                    "_text" = "http://youtube.com/?v=Zi_XLOBDo_Y";
                };