XPath匹配XML序列化的DataContract类
本文关键字:DataContract 序列化 匹配 XML XPath | 更新日期: 2023-09-27 17:57:52
我有一个DataContract
类MyDataContract
。我正在将它序列化为一个XML文件。稍后,在我的应用程序中的一个完全不同的"位置",我将加载这个文件。如果文件的内容符合特殊条件,我想在那里验证是否只加载。假设一个人只能拥有一辆车,那么我会存储一个人及其与该人车辆的关联。:-)
这里的DataContract
类:
namespace Test.DataContracts
{
[DataContract]
public class MyDataContract
{
[DataMember]
public string Identifier { get; set; }
[DataMember]
public Common.Person Person { get; set; }
[DataMember]
public Common.Vehicle Vehicle { get; set; }
}
}
namespace Test.DataContracts.Common
{
[DataContract]
public class Person
{
[DataMember]
public Global.Gender Gender { get; set; }
[DataMember]
public string Info { get; set; }
[DataMember]
public string Name { get; set; }
}
[DataContract]
public class Vehicle
{
[DataMember]
public string Info { get; set; }
[DataMember]
public string Name { get; set; }
[DataMember]
public string Vendor { get; set; }
}
}
namespace Test.DataContracts.Global
{
[DataContract]
public class Gender
{
[DataMember]
public int Type { get; set; }
[DataMember]
public string Name { get; set; }
}
}
生成以下序列化XML:
<?xml version="1.0" encoding="utf-8"?>
<MyDataContract xmlns="http://schemas.datacontract.org/2004/07/Test.DataContracts" xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
<Identifier>123456789</Identifier>
<Person xmlns:a="http://schemas.datacontract.org/2004/07/Test.DataContracts.Common">
<a:Gender xmlns:b="http://schemas.datacontract.org/2004/07/Test.DataContracts.Global">
<b:Name>Female</b:Name>
<b:Type>0</b:Type>
</a:Gender>
<a:Info>She is a beautiful lady.</a:Info>
<a:Name>Jane Doe</a:Name>
</Person>
<Vehicle xmlns:a="http://schemas.datacontract.org/2004/07/Test.DataContracts.Common">
<a:Info>A super great car.</a:Info>
<a:Name>Mustang 1983 Turbo GT</a:Name>
<a:Vendor>Ford</a:Vendor>
</Vehicle>
</MyDataContract>
现在我只想筛选出拥有任何福特(Vendor = Ford)
汽车的女性(Type = 0)
。我尝试了以下操作,但它总是导致匹配的false
。
string path = @"c:'janedoe.xml";
var xmlDoc = new XmlDocument();
xmlDoc.Load(path);
XmlNodeList xNodes = xmlDoc.SelectNodes(@"//namespace::*[not(. = ../../namespace::*)]");
var xNamespaceManager = new XmlNamespaceManager(xmlDoc.NameTable);
foreach (XmlNode node in xNodes)
{
if (!string.IsNullOrWhiteSpace(xNamespaceManager.LookupNamespace(node.LocalName))) continue;
xNamespaceManager.AddNamespace(node.LocalName, node.Value);
}
using (var fs = new FileStream(path, FileMode.Open))
{
var xDocument = new XPathDocument(fs);
var xNavigator = xDocument.CreateNavigator();
XPathExpression exp1 = xNavigator.Compile(string.Format("MyDataContract/Person/Gender/Type/descendant::*[contains(text(), '{0}')]", "0"));
exp1.SetContext(xNamespaceManager);
XPathExpression exp2 = xNavigator.Compile(string.Format("MyDataContract/Vehicle/Vendor/descendant::*[contains(text(), '{0}')]", "Ford"));
exp2.SetContext(xNamespaceManager);
if (xNavigator.Matches(exp1) && xNavigator.Matches(exp2))
{
Console.WriteLine("File '{0}' indicates a female person that owns a vehicle of Ford.", path);
}
else
{
Console.WriteLine("File '{0}' has no matches (female and Ford).", path);
}
}
有人能帮忙吗?
UPDATE 1-我已使用XmlNamespaceManager更改了代码。但在执行CCD_ 8时仍会导致CCD_。
如果您有XDocument,那么使用LINQ to XML:会更容易
var xdoc = XDocument.Load(memorystream);
// Making it simple, grab the first
var type = xdoc.Descendants(XName.Get("Type","http://schemas.datacontract.org/2004/07/Test.DataContracts.Global")).FirstOrDefault();
var vendor = xdoc.Descendants(XName.Get("Vendor", "http://schemas.datacontract.org/2004/07/Test.DataContracts.Common")).FirstOrDefault();
string path = "blah";
if (type != null && type.Value == "0" && vendor != null && vendor.Value == "Ford")
{
Console.WriteLine("File '{0}' indicates a female person that owns a vehicle of Ford.", path);
}
else
{
Console.WriteLine("File '{0}' has no matches (female and Ford).", path);
}
如果您确信XPath是唯一需要的解决方案:
using System.Xml.XPath;
var document = XDocument.Load(fileName);
var namespaceManager = new XmlNamespaceManager(new NameTable());
namespaceManager.AddNamespace("a", "http://schemas.datacontract.org/2004/07/Test.DataContracts.Global");
var name = document.XPathSelectElement("path", namespaceManager).Value;