LINQ读取XML

5 回答

• 21

  试试这个 .

  void Main()
  {
      StringBuilder result = new StringBuilder();
  
      //Load xml
      XDocument xdoc = XDocument.Load("data.xml");
  
      //Run query
      var lv1s = from lv1 in xdoc.Descendants("level1")
                 select new { 
                     Header = lv1.Attribute("name").Value,
                     Children = lv1.Descendants("level2")
                 };
  
      //Loop through results
      foreach (var lv1 in lv1s){
              result.AppendLine(lv1.Header);
              foreach(var lv2 in lv1.Children)
                   result.AppendLine("     " + lv2.Attribute("name").Value);
      }
  
      Console.WriteLine(result);
  }
  

  回复于 2024-05-16T05:28:48+08:00
• 8

  或者，如果您想要更通用的方法 - 即嵌套到“levelN”：

  void Main()
  {
      XElement rootElement = XElement.Load(@"c:\events\test.xml");
  
      Console.WriteLine(GetOutline(0, rootElement));  
  }
  
  private string GetOutline(int indentLevel, XElement element)
  {
      StringBuilder result = new StringBuilder();
  
      if (element.Attribute("name") != null)
      {
          result = result.AppendLine(new string(' ', indentLevel * 2) + element.Attribute("name").Value);
      }
  
      foreach (XElement childElement in element.Elements())
      {
          result.Append(GetOutline(indentLevel + 1, childElement));
      }
  
      return result.ToString();
  }
  

  回复于 2024-05-16T05:28:48+08:00
• 53

  一些简单的旧 foreach 循环提供了一个干净的解决方案：

  foreach (XElement level1Element in XElement.Load("data.xml").Elements("level1"))
  {
      result.AppendLine(level1Element.Attribute("name").Value);
  
      foreach (XElement level2Element in level1Element.Elements("level2"))
      {
          result.AppendLine("  " + level2Element.Attribute("name").Value);
      }
  }
  

  回复于 2024-05-16T05:28:48+08:00
• 216

  以下是一些基于@bendewey和@dommer示例的完整工作示例 . 我需要稍微调整一下才能使它工作，但是如果另一个LINQ noob正在寻找工作示例，那么你去：

  //bendewey's example using data.xml from OP
  using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  using System.Xml.Linq;
  
  class loadXMLToLINQ1
  {
      static void Main( )
      {
          //Load xml
          XDocument xdoc = XDocument.Load(@"c:\\data.xml"); //you'll have to edit your path
  
          //Run query
          var lv1s = from lv1 in xdoc.Descendants("level1")
             select new 
             { 
                 Header = lv1.Attribute("name").Value,
                 Children = lv1.Descendants("level2")
              };
  
          StringBuilder result = new StringBuilder(); //had to add this to make the result work
          //Loop through results
          foreach (var lv1 in lv1s)
          {
              result.AppendLine("  " + lv1.Header);
              foreach(var lv2 in lv1.Children)
              result.AppendLine("    " + lv2.Attribute("name").Value);
          }
          Console.WriteLine(result.ToString()); //added this so you could see the output on the console
      }
  }
  

  接下来：

  //Dommer's example, using data.xml from OP
  using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  using System.Xml.Linq;
  
  class loadXMLToLINQ
  {
  static void Main( )
      {
          XElement rootElement = XElement.Load(@"c:\\data.xml"); //you'll have to edit your path
          Console.WriteLine(GetOutline(0, rootElement));  
      }
  
  static private string GetOutline(int indentLevel, XElement element)
      {
          StringBuilder result = new StringBuilder();
          if (element.Attribute("name") != null)
          {
              result = result.AppendLine(new string(' ', indentLevel * 2) + element.Attribute("name").Value);
          }
          foreach (XElement childElement in element.Elements())
          {
              result.Append(GetOutline(indentLevel + 1, childElement));
          }
          return result.ToString();
      }
  }
  

  这些都使用csc.exe版本4.0.30319.1在VS2010中编译和工作，并提供完全相同的输出 . 希望这些可以帮助那些正在寻找代码工作示例的人 .

  编辑：添加了@eglasius的例子，因为它对我有用：

  //@eglasius example, still using data.xml from OP
  using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  using System.Xml.Linq;
  
  class loadXMLToLINQ2
  {
      static void Main( )
      {
          StringBuilder result = new StringBuilder(); //needed for result below
          XDocument xdoc = XDocument.Load(@"c:\\deg\\data.xml"); //you'll have to edit your path
          var lv1s = xdoc.Root.Descendants("level1"); 
          var lvs = lv1s.SelectMany(l=>
               new string[]{ l.Attribute("name").Value }
               .Union(
                   l.Descendants("level2")
                   .Select(l2=>"   " + l2.Attribute("name").Value)
                )
              );
          foreach (var lv in lvs)
          {
             result.AppendLine(lv);
          }
          Console.WriteLine(result);//added this so you could see the result
      }
  }
  

  回复于 2024-05-16T05:28:48+08:00
• 18

  XDocument xdoc = XDocument.Load("data.xml");
  var lv1s = xdoc.Root.Descendants("level1"); 
  var lvs = lv1s.SelectMany(l=>
       new string[]{ l.Attribute("name").Value }
       .Union(
           l.Descendants("level2")
           .Select(l2=>"   " + l2.Attribute("name").Value)
        )
      );
  foreach (var lv in lvs)
  {
     result.AppendLine(lv);
  }
  

  PS . 你必须在任何这些版本上使用.Root .

  回复于 2024-05-16T05:28:48+08:00