Question

Visual Studio在运行测试时创建“.trx”文件，我正在尝试处理这些文件中的XML。但是，当尝试使用Xpath表达式访问部分XML时，我得到了意想不到的结果。

以下代码包含“.trx”文件的缩减版本。这些文件包含xmlns="..."属性，似乎可以阻止Xpath访问。当xmlns...被删除时，访问工作并找到预期的节点。

如何更改名称空间管理器（manager）或代码中的Xpath（或其他内容），以便我可以获得与未修改的XML中的各种X路径匹配的节点列表。

我尝试在Xpath中添加manager.AddNamespace("ns", trxContent.NamespaceURI);并包含ns:，但没有成功。

using System;
using System.Xml;

namespace XpathXmlns
{
    class XpathXmlns
    {
        static string WithXmlns = @"<?xml version=""1.0"" encoding=""UTF-8""?>
<TestRun id=""111"" name=""someName"" runUser=""someUser"" xmlns=""http://microsoft.com/schemas/VisualStudio/TeamTest/2010""> tr1
  <TestSettings name=""Local1"" id=""222"" idx=""333""> ts2
    <Description>Description 1 context.</Description> ts3
  </TestSettings> tr4
  <TestSettings name=""Local2"" id=""333"" idx=""444""> ts5
    <Description>Description 2 context.</Description> ts6
  </TestSettings> tr7
</TestRun>
";

        static void Main(string[] args)
        {
            string WithoutXmlns = WithXmlns.Replace(@" xmlns=""http://microsoft.com/schemas/VisualStudio/TeamTest/2010""", "");

            ProcessXml("WithXmnns", WithXmlns);
            ProcessXml("WithoutXmlns", WithoutXmlns);
        }

        static int counter = 0;
        static XmlNamespaceManager manager;

        static void ProcessXml(string label, string xml)
        {
            Console.WriteLine(label);
            Console.WriteLine(xml);
            XmlDocument trxContent = new XmlDocument();
            trxContent.LoadXml(xml);

            XmlNameTable xmlnt = trxContent.NameTable;
            manager = new XmlNamespaceManager(xmlnt);
            //manager.AddNamespace("ns", trxContent.NamespaceURI);

            XmlNode root = trxContent.DocumentElement;

            Extract(trxContent, "//TestRun");
            Extract(trxContent, "//TestRun/TestSettings");
            Extract(trxContent, "//TestRun/TestSettings/Description");
            Extract(trxContent, "//Description");
            Extract(trxContent, "//TestSettings/@id");
            //Extract(trxContent, "//@id"); // This works OK, it finds the nodes in both cases.
            //Extract(trxContent, "//@idx"); // This works OK, it finds the nodes in both cases.
            Extract(trxContent, "//ns:TestRun");
            Extract(trxContent, "//ns:TestRun/TestSettings");
            Extract(trxContent, "//ns:TestRun/TestSettings/Description");
            Extract(trxContent, "//ns:Description");
            Extract(trxContent, "//ns:TestSettings/@id");
        }

        static void Extract(XmlDocument doc, string xpath)
        {
            counter = 0;
            ExtractNodes("doc-node", doc, xpath);
            ExtractDocNodes("doc", doc, xpath);
            Console.WriteLine();
        }

        private static void ExtractNodes(string source, XmlNode root, string xpath)
        {
            counter++;
            XmlNodeList nodes = root.SelectNodes(xpath, manager);
            ListFoundNodes(source, xpath, nodes);
        }
        private static void ExtractDocNodes(string source, XmlDocument root, string xpath)
        {
            counter++;
            XmlNodeList nodes = root.SelectNodes(xpath, manager);
            ListFoundNodes(source, xpath, nodes);
        }

        private static void ListFoundNodes(string source, string xpath, XmlNodeList nodes)
        {
            Console.WriteLine("    {0,2}: Get {1} from {2} {3}", counter, nodes.Count, source, xpath);
            foreach (XmlNode node in nodes)
            {
                Console.WriteLine("             Nodes  name='{0}'", node.Name ?? "__None__");
            }
        }
    }
}

Answer 1

Xmlns属性定义元素的xml名称空间。因此，您的TestRun元素（以及其下的所有元素）属于命名空间http://microsoft.com/schemas/VisualStudio/TeamTest/2010。首先，您必须将该命名空间添加到管理器：

XmlNameTable xmlnt = trxContent.NameTable;
manager = new XmlNamespaceManager(xmlnt);
manager.AddNamespace("ns", @"http://microsoft.com/schemas/VisualStudio/TeamTest/2010");

如果您不想对其进行硬编码，则可以使用根元素的命名空间：

XmlNode root = trxContent.DocumentElement;
XmlNameTable xmlnt = trxContent.NameTable;
manager = new XmlNamespaceManager(xmlnt);
manager.AddNamespace("ns", root.NamespaceURI);

然后，您必须在查询中使用您定义的名称空间前缀（ns）：

Extract(trxContent, "//ns:TestRun");
// note that all subelements (like TestSettings) are also prefixed
Extract(trxContent, "//ns:TestRun/ns:TestSettings");
Extract(trxContent, "//ns:TestRun/ns:TestSettings/ns:Description");
Extract(trxContent, "//ns:Description");
Extract(trxContent, "//ns:TestSettings/@id");

如果有xmlns =，如何查找XML节点

1 个答案: