如何使用 Linq 获取数据到 XML？

Question

我有以下 XML。获取数据的最佳方式是什么？

<?xml version='1.0' encoding='UTF-8'?>
<Root>
  <EmployeeDataRoot>
    <EmployeeData>
      <Employee_id>123456</Employee_id>
      <Employee_Status>A</Employee_Status>
      <Business_Unit>EN00</Business_Unit>
      <Cost_Center>0904/1992</Cost_Center>
      <Work_Location>DFW</Work_Location>
      <Location>DFW-HDQ1</Location>
      <Job_Category>0003</Job_Category>
      <Last_Name>John</Last_Name>
      <First_Name>Doe</First_Name>
      <Middle_Name />
      <Preferred_Name />
      <Position_Title>Programmer/Analyst</Position_Title>
      <Legal_Entity>EN00</Legal_Entity>
      <Department_Unit>IT HR &amp; Employee Technology</Department_Unit>
      <Run_Date>2016-12-12</Run_Date>
    </EmployeeData>
  </EmployeeDataRoot>
  <Footer_No_of_Records>
    <Records>1</Records>
  </Footer_No_of_Records>
</Root>

网上看了一些例子，试了两次都报错

object not set to an instance of an object

我查看了 Employee class 的属性以及节点是否有任何拼写错误，但没有发现任何拼写错误。我认为错误是我没有正确查询 XML 。

var xDoc = XDocument.Load(file.FullName);
listEmployee = 
    (from e in xDoc.Descendants("EmployeeData") 
      select new Employee
      {
        EmployeeID = e.Element("Employee_ID").Value,
        EmployeeStatus = e.Element("Employee_Status").Value,
        BusinessUnit = e.Element("Business_Unit").Value,
        CostCenter = e.Element("Cost_Center").Value,
        WorkLocation = e.Element("Work_Location").Value,
        Location = e.Element("Location").Value,
        JobCategory = e.Element("Job_Category").Value,
        FirstName = e.Element("First_Name").Value,
        LastName = e.Element("Last_Name").Value,
        LegalEntity = e.Element("Legal_Entity").Value
     }
   ).ToList();

我也试过了

listEmployee = 
    (from e in xDoc.Element("Root").Elements("EmployeeDataRoot/EmployeeData")
     select new Employee
     {
        EmployeeID = e.Element("Employee_ID").Value,
        EmployeeStatus = e.Element("Employee_Status").Value,
        BusinessUnit = e.Element("Business_Unit").Value,
        CostCenter = e.Element("Cost_Center").Value,
        WorkLocation = e.Element("Work_Location").Value,
        Location = e.Element("Location").Value,
        JobCategory = e.Element("Job_Category").Value,
        FirstName = e.Element("First_Name").Value,
        LastName = e.Element("Last_Name").Value,
        LegalEntity = e.Element("Legal_Entity").Value                                        
    }
  ).ToList();

Answer 1

你的尝试是对的，但是你"Employee_ID"写错了。试试这个：

var xDoc = XDocument.Load(file.FullName);
listEmployee = 
    (from e in xDoc.Descendants("EmployeeData") 
      select new Employee
      {
        EmployeeID = e.Element("Employee_id").Value,
        EmployeeStatus = e.Element("Employee_Status").Value,
        BusinessUnit = e.Element("Business_Unit").Value,
        CostCenter = e.Element("Cost_Center").Value,
        WorkLocation = e.Element("Work_Location").Value,
        Location = e.Element("Location").Value,
        JobCategory = e.Element("Job_Category").Value,
        FirstName = e.Element("First_Name").Value,
        LastName = e.Element("Last_Name").Value,
        LegalEntity = e.Element("Legal_Entity").Value
     }
   ).ToList();

如何使用 Linq 获取数据到 XML？

How to get data with Linq to XML?

.net

c#

xml

linq

linq-to-xml