Question

这是我的xml文档，看起来像这样

<?xml version="1.0" encoding="UTF-8"?>
<bookstore> 
<book category="cooking">
<title lang="en">Everyday Italian</title>
<author>Giada De Laurentiis</author>
<year updated="no" version="3.5">2005</year>
<price>30.00</price>
</book>
<book category="children">
<title lang="fr">Harry Potter</title>
<author>J K. Rowling</author>
<year updated="yes" version="2.0">2005</year>
<price>29.99</price>
</book>
</bookstore>

1 - 如何选择所有books并打印他们的element's text（标题，作者，...）？

2 - 如何只为每本书lang获取from title version和year的值？

3 - 如何选择所有books where category="cooking"并打印所有元素？

4 - 如何选择lang title为en的所有图书并打印所有元素值？

Answer 1

在这种情况下，这些版本的框架不支持XDocument class所以我们使用XmlDocument

 XmlDocument myXmlDoc = new XmlDocument();
 myXmlDoc.Load(@"c:\books.xml"); //wich is above you can use uri location
 XmlNodeList list = myXmlDoc.SelectNodes("/bookstore/book");
  //Selecting all book nodes then extract title author year  
  foreach (XmlNode mynode in list)
  {
  Console.WriteLine(mynode["title"].InnerText);
  Console.WriteLine(mynode["author"].InnerText);
  Console.WriteLine(mynode["year"].InnerText);
  Console.WriteLine(mynode["price"].InnerText);
  Console.WriteLine("------------");
  }
  //OUTPUT :
  Everyday Italian
  Giada De Laurentiis
  2005
  30.00
  -----------------------
  Harry Potter
  J K. Rowling
  2005
  29.99
  -----------------------
  //get the value of `lang` from `title` and `version` from `year` :
   foreach (XmlNode mynode in list)
   {
       Console.WriteLine(mynode["title"].Attributes["lang"].Value );
  Console.WriteLine(mynode["year"].Attributes["version"].Value );
 Console.WriteLine("------------");
        }
//OUTPUT : 

  en
  3.5
  ----------------
  fr
  2.0

  //get books that have category="children" and print all both firstane lastname .....
  XmlNodeList list = myXmlDoc.SelectNodes("/bookstore/book[@category='children']");
    foreach (XmlNode mynode in list)
      {
   Console.WriteLine(mynode["title"].InnerText );
   Console.WriteLine(mynode["author"].InnerText);
    Console.WriteLine(mynode["price"].InnerText);
        }

//OUTPUT:
Harry Potter
J K. Rowling
29.99

//select books where the `lang` of `title` is `en`

 XmlNodeList list = myXmlDoc.SelectNodes("/bookstore/book/title[@lang='en']");
              foreach (XmlNode mynode in list)
        {
            Console.WriteLine(mynode.ParentNode["title"].InnerText );
            Console.WriteLine(mynode.ParentNode["author"].InnerText);
            Console.WriteLine(mynode.ParentNode["price"].InnerText);
        }

    //OUTPUT:

    Everyday Italian
        Giada De Laurentiis
        30.00

如何在c＃2.0 / 3.0上选择指定值的xmlelements xmlnodes xmlattributes

1 个答案: