linq to xml：如何在C＃中的元素中获取标签的值

Question

I have following xml data. 我有以下xml数据。

<?xml version="1.0" encoding="utf-8" ?>
<mail>
  <id>signUpConfirmation</id>
  <subject>Activation</subject>
  <body>
Hi, You account is activated \nRegards
</body>
</mail>

I need to read value from <body> tag depending on id I pass. 我需要根据传递的id从<body>标记读取值。

This is what I have tried 这就是我尝试过的

var xml = File.ReadAllText("C:\\Users\\DELL\\Documents\\Visual Studio 2012\\Projects\\Website\\Website\\Files\\Mails.xml");

var str = XElement.Parse(xml);
var result = from mail in str.Elements("mail")
             where (string)mail.Element("id") == "signUpConfirmation"
             select (string)mail.Element("body");
log.Debug("mail data:" + result.First());

I get error : 我收到错误消息：

Sequence contains no elements. 序列不包含任何元素。

Also, I want to access the value of id tag as well in the same query. 另外，我也想在同一查询中访问id标签的值。

Answer 1

You have a couple of problems: 您有几个问题：

The id and body are not attributes but elements so you need to use the .Elements id和body不是属性而是元素，因此您需要使用.Elements
You are using the XElement to parse the xml. 您正在使用XElement解析xml。 It will start from the first element which is mail and then you are looking for child elements of it with the name of mail - which non exist. 它将从第一个元素mail ，然后您要查找其名称为mail子元素-不存在。 Use XDocument . 使用XDocument 。

Code: 码：

var result = (from mail in XDocument.Load("data.xml").Descendants("mail")
              where mail.Element("id").Value == "signUpConfirmation"
              select new {
                  Body = mail.Element("body").Value,
                  Subject = mail.Element("subject").Value
              }).ToList();

Answer 2

var str = XDocument.Parse("<?xml version=\"1.0\" encoding=\"utf-8\" ?><mail>  <id>signUpConfirmation</id>  <subject>Activation</subject>  <body>Hi, You account is activated \nRegards</body></mail>");

var result = from mail in str.Elements("mail")
where (string)mail.Element("id") == "signUpConfirmation"
select mail.Element("body");
result.FirstOrDefault();

Here is the code that work. 这是起作用的代码。

XDocument XDocument

instead of 代替

XElement X元素

End .Element as @DKR said. 以@DKR的形式结束.Element。

linq to xml：如何在C＃中的元素中获取标签的值

问题描述

2 个解决方案

解决方案1
4 已采纳 2016-10-26 07:36:32

解决方案2
1 2016-10-26 07:37:04

linq to xml：如何在C＃中的元素中获取标签的值

问题描述

2 个解决方案

解决方案1 4 已采纳 2016-10-26 07:36:32

解决方案2 1 2016-10-26 07:37:04

解决方案1
4 已采纳 2016-10-26 07:36:32

解决方案2
1 2016-10-26 07:37:04