C# LINQ 和 XML 获取子节点

Question

获取节点值时出现问题。不确定为什么以下代码无法这样做。

<?xml version="1.0" encoding="utf-8"?>
<?xml-stylesheet type='text/xsl' href='STIG_unclass.xsl'?>
<Benchmark xmlns:dsig="http://www.w3.org/2000/09/xmldsig#" xmlns:xhtml="http://www.w3.org/1999/xhtml" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:cpe="http://cpe.mitre.org/language/2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" id="Windows_7_STIG" xml:lang="en" xsi:schemaLocation="http://checklists.nist.gov/xccdf/1.1 http://nvd.nist.gov/schema/xccdf-1.1.4.xsd http://cpe.mitre.org/dictionary/2.0 http://cpe.mitre.org/files/cpe-dictionary_2.1.xsd" xmlns="http://checklists.nist.gov/xccdf/1.1">
    <status date="2015-06-16">accepted</status>
    <title>Windows 7 Security Technical Implementation Guide</title>
    <description>
        The Windows 7 Security Technical Implementation Guide (STIG) is published as a tool to improve the security of Department of Defense (DoD) information systems.  The requirements were developed from DoD consensus, as well as the Windows 7 Security Guide and security templates published by Microsoft Corporation.  Comments or proposed revisions to this document should be sent via e-mail to the following address:  disa.stig_spt@mail.mil.
    </description>
    <notice id="terms-of-use" xml:lang="en">Developed_by_DISA_for_the_DoD</notice>
    <reference href="http://iase.disa.mil">
        <dc:publisher>DISA, Field Security Operations</dc:publisher>
        <dc:source>STIG.DOD.MIL</dc:source>
    </reference>
    <plain-text id="release-info">Release: 20 Benchmark Date: 24 Jul 2015</plain-text>
</Benchmark>

示例 XML 文件。

下面是我的代码。

String Title = LoadedXML.Element("Benchmark").Attribute("id").Value;
var XMLData = LoadedXML.Element("Benchmark").Elements("plain-text")
                 .Single(release => release.Attribute("id").Value == "release-info").Value;

有没有办法可以同时获取多个节点值？喜欢一次获得标题和发行值(value)而不是分别获得一个吗？

Answer 1

您的代码失败是因为您的 XML 包含 Namespace 并且您无法直接访问您的节点。如果您想确认这一点，只需查询 LoadedXML.Elements() 并检查调试器中的值，您可以清楚地看到那里的命名空间:-

因此，您需要声明命名空间并使用它:-

XNamespace ns = "http://checklists.nist.gov/xccdf/1.1";

如果您希望同时获取两个值，您可以将其投影为匿名类型，如下所示:-

var result = LoadedXML.Root.Elements(ns + "plain-text")
                      .Where(x => (string)x.Attribute("id") == "release-info")
                      .Select(x => new
                             {
                                 Title = (string)x.Document.Root.Attribute("id"),
                                 XMLData = x.Value
                             }).FirstOrDefault();

此查询给出以下输出:-