c# 读取xml 冒号问题的解决方法

public void bindXml(string xmlUrl)
{
System.Xml.XmlDocument doc = new System.Xml.XmlDocument();
doc.Load( System.AppDomain.CurrentDomain.Basedirectory+"kkjj.xml");
//doc.Load(xmlUrl);
doc.SelectNodes("/rss/channel");
System.Xml.XmlNode root = doc.DocumentElement;
System.Xml.XmlNode xn = root.SelectSingleNode("/rss/channel");
outStr += "相册名称：" + xn.SelectSingleNode("title").InnerText;//相册名称
outStr += "<br>相册url：" + xn.SelectSingleNode("link").InnerText;//相册url
outStr += "<br>相册图片：<img src='" + xn.SelectSingleNode("image/url").InnerText + "' />";//相册首页图片

//outStr += "<br><img src='" + xn.SelectNodes("item")[0].SelectSingleNode("enclosure").Value + "'>";
System.Xml.XmlNodeList xnl = xn.SelectNodes("item");
outStr += "<br>相册图片数：" + xnl.Count.ToString() + "张";

System.Xml.XmlNamespaceManager nsmanager = new System.Xml.XmlNamespaceManager(doc.NameTable);
nsmanager.AddNamespace("media", "http://search.yahoo.com/mrss/");

// 创建包含 XPATH 表达式的字符串以进行计算。
string exprString = String.Format("// {0}:group", "media");

System.Xml.XmlNodeList nodelist = doc.SelectNodes(exprString, nsmanager);

outStr += "<br>media:title:"+nodelist[0].SelectSingleNode("media:title",nsmanager).Attributes["type"].InnerText;
// for(int i=0;i<xnl.Count;i++)
// {
// outStr += "<br> <img src='"+xnl[i].SelectSingleNode("enclosure").Attributes["url"].InnerText+"' />";
// }
}

<media:group>
<media:title type="plain">02.JPG</media:title>
<media:description type="plain" />
<media:keywords />
<media:thumbnail url="http://lh3.google.com/pengpengsay/R3C96dqJBUI/AAAAAAAAAEo/j3csPO0ig7o/s72/02.JPG" height="48" width="72" />
<media:thumbnail url="http://lh3.google.com/pengpengsay/R3C96dqJBUI/AAAAAAAAAEo/j3csPO0ig7o/s144/02.JPG" height="96" width="144" />
<media:thumbnail url="http://lh3.google.com/pengpengsay/R3C96dqJBUI/AAAAAAAAAEo/j3csPO0ig7o/s288/02.JPG" height="192" width="288" />
<media:content url="http://lh3.google.com/pengpengsay/R3C96dqJBUI/AAAAAAAAAEo/j3csPO0ig7o/02.JPG" height="400" width="600" type="image/jpeg" medium="image" />
<media:credit>成刚</media:credit>
</media:group>