迭代使用foreach XmlNodeList循环到达的XmlNode

您可以这样做。我们的想法是迭代所有<ns>节点，以确定值为"CounterSales"的节点的索引。然后，我们使用该索引来选择相关的<r>。

我还更改了初始<ni>的选择方式。按照您的方式，值"CounterSales"出现在OuterXml中的任何地方可能会给您一个错误的匹配。这种方法使用包含谓词的XPath表达式。

XmlElement root = doc.DocumentElement;
// Use XPath to find <ni> that contain CounterSales, rather than use string comparison
XmlNodeList nodes = root.SelectNodes("//nd/ni[ns='CounterSales']");
foreach (XmlNode node in nodes)
{
    XmlNodeList nsNodes = node.SelectNodes("ns");
    // Get index of "CountersSales" within <ni>
    int index = 0;
    while (index < nsNodes.Count)
    {
        if (nsNodes[index].InnerText == "CounterSales")
            break;
        index++;
    }
    // Search through <nv>
    XmlNodeList nvNodes = node.SelectNodes("nv");
    foreach (XmlElement nvNode in nvNodes)
    {
        XmlNode nadNode = nvNode.SelectSingleNode("nad");
        // Get the stuff after the last equals sign. Possibly use regex here instead.
        string id = nadNode.InnerText.Substring(nadNode.InnerText.LastIndexOf('=') + 1);
        // XPathQuery for r element at our index (position in xpath is 1-based, rather than 0-based like C#)
        string rQuery = String.Format("r[position() = {0}]", index + 1);
        XmlNode rNode = nvNode.SelectSingleNode(rQuery);
        Console.WriteLine("{0}, {1}", id, rNode.InnerText);
    }
}

使用linq辅助函数使代码非常简单

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Xml.Linq;
using System.Text.RegularExpressions;
namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            string input =
                "<ni>" +
                    "<nss>20150927</nss>" +
                    "<gp>Addon</gp>" +
                    "<ns>CounterBlah1</ns>" +
                    "<ns>CounterBlah2</ns>" +
                    "<ns>CounterSales</ns>" +
                    "<ns>CounterBlah4</ns>" +
                    "<ns>CounterBlah5</ns>" +
                    "<ns>CounterBlah6</ns>" +
                    "<nv>" +
                        "<nad>Style=1,Rfu=1,Id=132</nad>" +
                        "<r>0</r>" +
                        "<r>15</r>" +
                        "<r>8</r>" +
                        "<r>3</r>" +
                        "<r>2</r>" +
                        "<r>2</r>" +
                    "</nv>" +
                    "<nv>" +
                        "<nad>Style=1,Rfu=1,Id=433</nad>" +
                        "<r>0</r>" +
                        "<r>15</r>" +
                        "<r>30</r>" +
                        "<r>3</r>" +
                        "<r>2</r>" +
                        "<r>2</r>" +
                    "</nv>" +
                    "<nv>" +
                        "<nad>Style=1,Rfu=1,Id=665</nad>" +
                        "<r>0</r>" +
                        "<r>15</r>" +
                        "<r>90</r>" +
                        "<r>3</r>" +
                        "<r>2</r>" +
                        "<r>2</r>" +
                    "</nv>" +
                "</ni>";
            XElement ni = XElement.Parse(input);
            var results1 = ni.Descendants("nv").Select(x => new
            {
                nad = x.Element("nad").Value,
                r = x.Elements("r").Select(y => y.Value).ToList()
            }).ToList();
            var results2 = results1.Select(x => new {
                Id = Helper(x.nad, "Id"),
                r = int.Parse(x.r[2])
            }).ToList();
        }
        static int? Helper(string csv, string name)
        {
            int? results = null;
            string pattern = @"(?'name''w+)=(?'value''d+)";
            MatchCollection matches = Regex.Matches(csv, pattern);
            foreach(Match match in matches)
            {
                string csvName = match.Groups["name"].Value;
                if(csvName == name)
                {
                    results = int.Parse(match.Groups["value"].Value);
                    break;
                }
            }
            return results;
        }
    }
}
​