读取XML(来自字符串)并获取一些字段 - 读取XML的问题

Question

我有这个XML(存储在一个C#字符串中myXML)

<?xml version="1.0" encoding="utf-16"?>
<myDataz xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <listS>
    <sog>
      <field1>123</field1>
      <field2>a</field2>
      <field3>b</field3>
    </sog>
    <sog>
      <field1>456</field1>
      <field2>c</field2>
      <field3>d</field3>
    </sog>
  </listS>
</myDataz>

我想浏览所有<sog>元素.对于他们每个人,我想打印孩子<field1>.

所以这是我的代码:

XmlDocument xmlDoc = new XmlDocument();
string myXML = "<?xml version=\"1.0\" encoding=\"utf-16\"?><myDataz xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\"><listS><sog><field1>123</field1><field2>a</field2><field3>b</field3></sog><sog><field1>456</field1><field2>c</field2><field3>d</field3></sog></listS></myDataz>"
xmlDoc.Load(myXML);
XmlNodeList parentNode = xmlDoc.GetElementsByTagName("listS");
foreach (XmlNode childrenNode in parentNode)
{
    HttpContext.Current.Response.Write(childrenNode.SelectSingleNode("//field1").Value);
}

但似乎我无法读取字符串作为XML？我明白了System.ArgumentException

Answer 1

你应该使用LoadXml方法,而不是Load:

xmlDoc.LoadXml(myXML); 

Load方法试图从文件加载xml并从字符串加载LoadXml.你也可以使用XPath:

XmlDocument xmlDoc = new XmlDocument();
xmlDoc.LoadXml(xml);

string xpath = "myDataz/listS/sog";
var nodes = xmlDoc.SelectNodes(xpath);

foreach (XmlNode childrenNode in nodes)
{
    HttpContext.Current.Response.Write(childrenNode.SelectSingleNode("//field1").Value);
} 

Answer 2

使用Linq-XML,

XDocument doc = XDocument.Load(file);

var result = from ele in doc.Descendants("sog")
              select new
              {
                 field1 = (string)ele.Element("field1")
              };
 foreach (var t in result)
  {
      HttpContext.Current.Response.Write(t.field1);
  }

或者:获取<sog>标记的节点列表.

 XmlDocument xmlDoc = new XmlDocument();
 xmlDoc.Load(myXML);
 XmlNodeList parentNode = xmlDoc.GetElementsByTagName("sog");
 foreach (XmlNode childrenNode in parentNode)
  {
    HttpContext.Current.Response.Write(childrenNode.SelectSingleNode("field1").InnerText);
   }

Answer 3

其他答案已有几年的历史了(并且不适用于Windows Phone 8.1)所以我想我会选择其他选项.我用它来解析Windows Phone应用程序的RSS响应:

XDocument xdoc = new XDocument();
xdoc = XDocument.Parse(xml_string);