c#通过xpath读取xml示例

需要修改Main方法第一行代码的路径为你的books.xml文件绝对路径或相对路径。代码演示了XPath各种语法的使用情况

books.xml

  <book category="COOKING">
    <title lang="en">Everyday Italian</title>
    <author>Giada De Laurentiis</author>
    <year>2005</year>
    <price>30.00</price>
  </book>

  <book category="CHILDREN">
    <title lang="en">Harry Potter</title>
    <author>J K. Rowling</author>
    <year>2005</year>
    <price>29.99</price>
  </book>

  <book category="WEB">
    <title lang="en">XQuery Kick Start</title>
    <author>James McGovern</author>
    <author>Per Bothner</author>
    <author>Kurt Cagle</author>
    <author>James Linn</author>
    <author>Vaidyanathan Nagarajan</author>
    <year>2003</year>
    <price>49.99</price>
  </book>

  <book category="WEB">
    <title lang="en">Learning XML</title>
    <author>Erik T. Ray</author>
    <year>2003</year>
    <price>39.95</price>
  </book>

</bookstore>
</div>

主程序

namespace XmlProcessTest
{
    public class Program
    {
        /// <summary>
        /// 加载XML文件
        /// </summary>
        /// <param name="xmlFilePath">XML文件路径</param>
        /// <returns></returns>
        public static XmlDocument LoadXmlDoc(string xmlFilePath)
        {
            var xmlDoc = new XmlDocument();
            xmlDoc.Load(xmlFilePath);

            return xmlDoc;
        }

        /// <summary>
        /// 根据指定的XPath表达式获取XML结点列表
        /// </summary>
        /// <param name="xmlDoc"></param>
        /// <param name="xpathExpr"></param>
        /// <returns></returns>
        public static XmlNodeList GetXmlNodes(XmlDocument xmlDoc, string xpathExpr)
        {
            if (xmlDoc == null)
                return null;

            return xmlDoc.SelectNodes(xpathExpr);
        }

        public static string GetXmlNodeInfo(XmlNode node, string type="xml")
        {
            if (node == null)
                return "Empty node or error node";

            string xmlNodeInfo = null;
            switch (type)
            {
                case "text":
                    xmlNodeInfo = node.InnerText;
                    break;
                default:
                    xmlNodeInfo = node.InnerXml;
                    break;
            }

            return xmlNodeInfo;
        }

        public static void Main(string[] args)
        {
            var xmlDoc = LoadXmlDoc(@"你的books.xml文件路径");

            var rootExpr = "/bookstore";   //  根节点对应的XPath表达式
            var rootNode = GetXmlNodes(xmlDoc, rootExpr);   //
            Console.WriteLine("XPath表达式为 /bookstore，根节点bookstore的所有子节点XML内容如下：");
            Console.WriteLine(GetXmlNodeInfo(rootNode[0]));

            Console.WriteLine();

            var allBooksExpr = "/bookstore/book"; // 根节点bookstore的子元素的所有子节点
            var bookNodes = GetXmlNodes(xmlDoc, allBooksExpr);
            Console.WriteLine("XPath表达式为 bookstore/book，book节点共有：" + bookNodes.Count);

            Console.WriteLine();

            var anyBookExpr = "//book"; // 选取所有book子元素，而不管它们在文档中的位置
            var anyBookNodes = GetXmlNodes(xmlDoc, anyBookExpr);
            Console.WriteLine("XPath表达式为 //book，book节点共有：" + anyBookNodes.Count);
            Console.WriteLine(anyBookNodes[0].InnerXml);
    &nb