带有命名空间的C# XPATH

Question

这是XML文件，我想获取"cron-expression“的Xpath，实际上我想更改内部文本。我已经尝试了很多方法，但都不起作用，我只想得到直接的答案。我尝试过local-name和XmlnamespaceManager.addnamespace，但它不起作用。

<!-- This file contains job definitions in schema version 2.0 format -->

<job-scheduling-data 
xmlns="http://quartznet.sourceforge.net/JobSchedulingData" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0">

  <processing-directives>
    <overwrite-existing-data>true</overwrite-existing-data>
  </processing-directives>

  <schedule>

    <job>
        <name>SampleJob</name>
        <group>SampleGroup</group>
        <description>My job</description>
        <job-type>Quartz.Server.SampleJob, Quartz.Server</job-type>
        <durable>true</durable>
        <recover>false</recover>
    </job>

    <trigger>
     <cron>
        <name>SampleTrigger</name>
        <group>SampleGroup</group>
        <description>Simple trigger to simply fire sample job</description>
        <job-name>SampleJob</job-name>
        <job-group>SampleGroup</job-group>
        <misfire-instruction>SmartPolicy</misfire-instruction>
        <cron-expression>0 * 15 * * ?</cron-expression>
      </cron>
    </trigger>
  </schedule>
</job-scheduling-data>

这是我的代码。不是工作。

 protected void Button2_Click(object sender, EventArgs e)
    {
        XmlDocument doc = new XmlDocument();
        doc.Load("D:/Chrome/Quartz.NET-2.4.1/src/Quartz.Examples/quartz_jobs.xml");
        XmlNamespaceManager xnm = new XmlNamespaceManager(doc.NameTable);
        xnm.AddNamespace("h", 
"http://quartznet.sourceforge.net/JobSchedulingData");

   XmlNode XN = doc.SelectSingleNode("h:job-scheduling-data/h:schedule/h:trigger/h:cron/h:cron-expression",xnm);


 //     XmlNode XN = doc.SelectSingleNode("/*[local-name() = 'job-scheduling-data']/*[local-name() = 'schedule']/*[local-name() = 'trigger']/*[local-name() = 'cron']/*[local-name() = 'cron-expression']");
    XN.InnerText = "0";
    doc.Save("D:/Chrome/Quartz.NET-2.4.1/src/Quartz.Examples/quartz_jobs.xml");//
}

Answer 1

尝试使用XDocument -(“使用System.Xml.Linq")

var doc = XDocument.Load(File.Open("D:/Chrome/Quartz.NET-2.4.1/src/Quartz.Examples/quartz_jobs.xml",FileMode.Open));

var childElements = doc.DescendantNodes().Where(n => n.NodeType == XmlNodeType.Element).Select(n => (n as XElement));
var cronElement = childElements.Where(e => e.Name.LocalName == "cron-expression").FirstOrDefault();
cronElement.SetValue("0");

doc.Save("D:/Chrome/Quartz.NET-2.4.1/src/Quartz.Examples/quartz_jobs.xml");