c# - 使用 C# 查找具有路径和 id 属性值的单个节点

Question

假设我有以下 xml，我想获取 id 为 Pkg1 的单个节点的版本属性值，预计为 1.2.3.

<project>
   <nugets id='test'> </nugets>
   <packages>
      <package id='test1' version='1'/>
      <package id='Pkg1' version='1.2.3'/>
      <package id='Pkg1Test' version='4.5.6'/>
   </packages>
</project>

下面是我的尝试，但是目标节点在 OuterXml 的字段中作为目标节点的字符串:

XmlDocument xmlDoc = new XmlDocument();
xmlDoc.LoadXml(xmlStr);
string path = "project/packages/package[@id='Pkg1']"; // target node has id=Pkg1
var targetNode = xmlDoc.SelectSingleNode(path);
Console.WriteLine($"{targetNode.OuterXml}"); // prints out the target node as string.

这似乎可行:string version = targetN.Attributes["version"].Value，这是获取属性值的正确方法吗，为什么节点在 targetNode 中.OuterXml?

Answer 1

这是一个工作代码来获得你所需要的:

private const string str = @"
<project>
   <nugets id='test'> </nugets>
   <packages>
      <package id='test1' version='1'/>
      <package id='Pkg1' version='1.2.3'/>
      <package id='Pkg1Test' version='4.5.6'/>
   </packages>
</project>";
        private static void Test()
        {
            var el = XElement.Parse(str);
            var packages = el.Element("packages")?
                .Elements("package")
                .ToList();
            var package = packages?
                .FirstOrDefault(x => x.Attribute("id")?.Value == "Pkg1");
            var id = package?.Attribute("version")?.Value;
            Console.Write(id);
        }