我有一个应用程序，该应用程序接收多个xml文件并执行查找以创建一个csv文件，我注意到数据并不总是100％，即缺少结果或2，所以我想出了我处理该文件的方式数据不正确且不正确，因此非常感谢这里专家提供的帮助。
小型XML示例：
<?xml version="1.0" encoding="utf-8"?>
<lookupdb xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:sample:lookupdb:0.1">
<References>
<Reference id="3cb7ceb0-43c7-4c67-a7fb-fffb32fc71c4">
<Vehicle>Beach_Buggy_01</Vehicle>
<Engineers>
<Engineer>Joe Bloggs</Engineer>
</Engineers>
<IsActive>true</IsActive>
<Owner>Bill Bloggs</Owner>
<Serviced>True</Serviced>
<OwnerName>Bill</OwnerName>
<CostID>ABCDEF123456</CostID>
<FuelType>Petrol</FuelType>
<Phone>1234567890</Phone>
<Address>Some Address</Address>
</Reference>
<Reference id="d1053bd3-a1cb-4fb4-a7d5-ffee3e10ffdb">
<Vehicle>Transit</Vehicle>
<Engineers>
<Engineer>Joe Bloggs2</Engineer>
</Engineers>
<IsActive>true</IsActive>
<Owner>Andy Bloggs</Owner>
<Serviced>True</Serviced>
<OwnerName>Andy</OwnerName>
<CostID>9345089</CostID>
<FuelType>Petrol</FuelType>
<Phone>1234567890</Phone>
<Address>Some Address4</Address>
</Reference>
<Reference id="30f8cfe8-40fd-4c99-9c7d-5ab98f8e5620">
<Vehicle>Ford Fiesta</Vehicle>
<Engineers>
<Engineer>Steve Bloggs</Engineer>
</Engineers>
<IsActive>true</IsActive>
<Owner>Sarah H</Owner>
<Serviced>True</Serviced>
<OwnerName>Bill</OwnerName>
<CostID>834hsdfgs</CostID>
<FuelType>Petrol</FuelType>
<Phone>1234567890</Phone>
<Address>Some Address3</Address>
</Reference>
</References>
<Sessions>
<RentalSession id="cc5d9960-3a80-4fd9-b7d6-0963198567c3">
<VehicleRefId>3cb7ceb0-43c7-4c67-a7fb-fffb32fc71c4</VehicleRefId>
<RentalPeriod startDate="2018-10-02T07:46:34Z" endDate="2018-10-02T08:27:36Z" />
<HiringInfo HireId="2e428f42-f8f1-4603-9570-fed1fa78e470" customerId="1929936734" customerRefId="6da73407-f443-491d-9cad-c4fed9bfb71f" />
<Notes>Vehicle Broke Down Recovery ordered</Notes>
<VehicleGroup>ATV</VehicleGroup>
</RentalSession>
<RentalSession id="829221a2-196e-403a-bdcb-9759959cfa70">
<VehicleRefId>3cb7ceb0-43c7-4c67-a7fb-fffb32fc71c4</VehicleRefId>
<RentalPeriod startDate="2018-10-03T07:46:34Z" endDate="2018-10-04T08:27:36Z" />
<HiringInfo HireId="4fb2cd21-9f48-44de-ae72-01ce4eeccdf9" customerId="2929936735" customerRefId="0a2d3d8b-ab06-4cd1-9ec5-aea4ac3f6da3" />
<Notes>Returned on Time no Damage</Notes>
<VehicleGroup>ATV</VehicleGroup>
</RentalSession>
<RentalSession id="68a6b485-d30a-439a-8081-8c09f724d23b">
<VehicleRefId>d1053bd3-a1cb-4fb4-a7d5-ffee3e10ffdb</VehicleRefId>
<RentalPeriod startDate="2018-10-05T07:46:34Z" endDate="2018-10-05T08:27:36Z" />
<HiringInfo HireId="c4022764-7fc2-4415-97bf-57d616e3b8bd" customerId="3929936736" customerRefId="cb260bfc-34c1-4ac5-befa-17f69b2406bb" />
<Notes>Scratch to Door Charges applied</Notes>
<VehicleGroup>VANS</VehicleGroup>
</RentalSession>
<RentalSession id="c4083f9a-65ee-4693-8488-e299271064b1">
<VehicleRefId>30f8cfe8-40fd-4c99-9c7d-5ab98f8e5620</VehicleRefId>
<RentalPeriod startDate="2018-10-09T07:46:34Z" endDate="2018-10-09T08:27:36Z" />
<HiringInfo HireId="cb260bfc-34c1-4ac5-befa-17f69b2406bb" customerId="4929936737" customerRefId="c4022764-7fc2-4415-97bf-57d616e3b8bd" />
<Notes>Generally a rubbish vehicle</Notes>
<VehicleGroup>Small Cars</VehicleGroup>
</RentalSession>
</Sessions>
</lookupdb>
用户名是程序的主要查找内容，同时还需要工程师，因为会话中的VehicleRefId与参考ID相匹配，而大部分数据都是从租用会话中获取的；但是，从一些本地测试中，我发现首先获取会话数据似乎更好，但不能完全确定采用这种方法，这是我认为需要查看的代码：
1：获取租赁数据
var result = xDoc.Descendants().Descendants(ns + "RentalSession")
.Where(x => x.Element(ns + "VehicleRefId").Value != null)
.Select(x => new
{
_VehicleRefId = GetResultValue(true, x, "VehicleRefId", "VehicleRefId", "Vehicle Reference ID"),
_RentalSessionId = GetResultValue(false, x, "RentalSession", "id", "Session ID"),
_startDate = GetResultValue(false, x, "RentalPeriod", "startDate", "Start date"),
_endDate = GetResultValue(false, x, "RentalPeriod", "endDate", "End date"),
_VehicleGroup = GetResultValue(true, x, "VehicleGroup", "VehicleGroup", "Vehicle Group"),
_Notes = GetResultValue(true, x, "Notes", "Notes", "Event Notes")
}).ToList().Distinct();
2：在出租数据查询中看到的方法：
private string GetResultValue(bool isNode, XElement atrr_value,string nodeName, string xattr_Name, string value_text)
{
string retValue = "";
try
{
switch(isNode)
{
case true:
retValue = !string.IsNullOrEmpty((string)atrr_value.Element(ns + nodeName).Value)
? (string)atrr_value.Element(ns + nodeName).Value
: $"No {value_text} Found.";
break;
default:
if(nodeName == "RentalSession")
{
retValue = !string.IsNullOrEmpty((string)atrr_value.Attribute(xattr_Name).Value)
? (string)atrr_value.Attribute(xattr_Name).Value
: $"No {value_text} Found.";
}
else
{
retValue = !string.IsNullOrEmpty((string)atrr_value.Element(ns + nodeName).Attribute(xattr_Name).Value)
? (string)atrr_value.Element(ns + nodeName).Attribute(xattr_Name).Value
: $"No {value_text} Found.";
}
break;
}
}
catch(Exception rex)
{
retValue = "null";
}
return retValue;
}
3：获取所有者和工程师数据：
foreach(var itemData in result)
{
try
{
var references = xDoc.Descendants().Descendants(ns + "Reference")
.Where(
a => a.Attribute("id").Value == itemData._VehicleRefId
)
.Select(a => new
{
_OwnerName = a.Element(ns + "OwnerName").Value,
_Engineer = a.Elements(ns + "Engineers").Descendants(ns + "Engineer").Select(e => e.Value).Single()
}).FirstOrDefault();
... Further parsing
catch (Exception xEx)
{
//some error handling stuff
}
}
非常感谢您的帮助，以便了解我在学习和精简此部分代码方面的不足。
非常感谢。
编辑：上面的xml仅显示数据的一部分，将有多个引用和会话，并且某些会话将匹配相同的引用。
答案 0 :(得分：1)
不要使用“ Value”属性，该属性在元素为null时会出现问题。而是在下面执行强制转换代码
var result = xDoc.Descendants().Descendants(ns + "RentalSession")
.Where(x => x.Element(ns + "VehicleRefId").Value != null)
.Select(x => new
{
_VehicleRefId = (string)x.Element("VehicleRefId"),
_RentalSessionId = (string)x.Element("RentalSession),
_startDate = (DateTime)x.Element("RentalPeriod),
_endDate = (DateTime)x.Element("RentalPeriod"),
_VehicleGroup = (string)x.Element("VehicleGroup"),
_Notes = (string)x.Element("Notes")
}).ToList().Distinct();
答案 1 :(得分：1)
从https://github.com/hyperledger/composer/issues/4375获取与XmlSerializer兼容的类。
将您的Xml复制并粘贴到上面链接的编辑器中，然后单击Convert按钮以获取您的课程。
通过这种方法，您可以通过类对象的[Dot]表示法轻松获取所需的xml节点或属性值。
在这里，我创建了一个控制台应用程序用于演示。
class Program
{
static void Main(string[] args)
{
var xml = System.IO.File.ReadAllText(@"C:\Users\Nullplex6\source\repos\ConsoleApp4\ConsoleApp4\Files\XMLFile9.xml");
var serializer = new XmlSerializer(typeof(Lookupdb));
using (var reader = new StringReader(xml))
{
Lookupdb lookupdb = (Lookupdb)serializer.Deserialize(reader);
//Here you can get any xml node and attribute value of single "RentalSession" in "Sessions" by passig id to where clause
RentalSession rentalSession = lookupdb.Sessions.RentalSession.Where(x => x.Id == "68a6b485-d30a-439a-8081-8c09f724d23b").FirstOrDefault();
Console.WriteLine("Id: " + rentalSession.Id);
Console.WriteLine("VehicleRefId: " + rentalSession.VehicleRefId);
Console.WriteLine("EndDate: " + rentalSession.RentalPeriod.EndDate);
Console.WriteLine("VehicleGroup: " + rentalSession.VehicleGroup);
Console.WriteLine();
//Here you can get any xml node and attribute value of single "Reference" in "References" by passig id to where clause
Reference reference = lookupdb.References.Reference.Where(x => x.Id == "d1053bd3-a1cb-4fb4-a7d5-ffee3e10ffdb").FirstOrDefault();
Console.WriteLine("OwnerName: " + reference.OwnerName);
Console.WriteLine("Engineer: " + reference.Engineers.Engineer);
Console.ReadLine();
}
}
}
输出：