如何閱讀和編輯XML節點

Question

我對所有這些都相當新，並且很難找到答案，所以任何正確方向的指針都會很棒。

我有一個我無法控制的系統的XML文件，它產生如下：

<?xml version="1.0" ?>
<WatchConfig>
<ProcessList>
    <Process>
        <RunOnDesktop>0</RunOnDesktop>
        <DaysToKeepBackup>10</DaysToKeepBackup>
        <Scheduler>
            <Active>-1</Active>
            <Startup>0</Startup>
            <SelfRepl>0</SelfRepl>
            <MaxPercent>0</MaxPercent>
            <Delay>4</Delay>
            <AsSoon>-1</AsSoon>
            <OneTime>0</OneTime>
            <Period>0</Period>
            <Week>1</Week>
            <Interval>2</Interval>
        </Scheduler>
        <UniqueName>0ZISFZL6O6S5001</UniqueName>
        <Name>Process1</Name>
        <Group/>
        <MetaFileName/>
                 </Process>
    <Process>
        <RunOnDesktop>0</RunOnDesktop>
        <DaysToKeepBackup>10</DaysToKeepBackup>
        <Scheduler>
            <Active>0</Active>
            <Startup>0</Startup>
            <SelfRepl>0</SelfRepl>
            <MaxPercent>20</MaxPercent>
            <Delay>4</Delay>
            <AsSoon>-1</AsSoon>
            <OneTime>0</OneTime>
            <Period>0</Period>
            <Week>1</Week>
            <Interval>2</Interval>
        </Scheduler>
        <UniqueName>00ZJENPXPX1KL07</UniqueName>
        <Name>Process2</Name>
        <Group/>
        <MetaFileName/>
    </Process>
</ProcessList>
</WatchConfig>

我希望能夠做的是閱讀這個並修改Scheduler節點下的Active值，理想情況下能夠指定我想要修改的進程的名稱。（在這個例子中有兩個）

Answer 1

最簡單的XLinq：

var doc = XDocument.Load(fileName);
var p = doc.Descendants("Process")
      .Where(e => e.Element("UniqueName").Value == procName )
      .Single();

var a = p.Element("Scheduler").Element("Active");            
a.Value = "+1";

doc.Save(outFileName);

Answer 2

也許你可以試試像LINQ這樣的東西

你可以這樣做來加載XML

using System;
using System.Collections.Generic;
using System.Linq;
using System.Xml.Linq;
public class EmployeeServices
{
    XElement _empXml = XElement.Load(@"employees.xml");
}

//然后查詢信息你可以做到這一點

public List<string> GetDepartments()
{
  //query the XML and group by department
   // select only the departments in the group
   var deptQuery =
   from emp in _empXml.Descendants("Employee")
   group emp by emp.Element("Department").Value
   into empGroup
   select empGroup.First().Element("Department").Value;
   return deptQuery.ToList();
}

這是MCTS書中的一個例子，希望它有所幫助。