XElement和List <T>

Question

我有一个具有以下属性的类:

public class Author {
  public string FirstName { get; set; }
  public string LastName { get; set; }
}

接下来,我有一个像这样的作者列表:

List<Author> authors = new List<Author> ();

authors.add(
  new Author { 
    FirstName = "Steven",
    LastName = "King"
  });

authors.add(
  new Author { 
    FirstName = "Homer",
    LastName = ""
  });

现在,我正在尝试使用Linq to XML来生成表示我的作者列表的XML.

new XElement("Authors",
  new XElement("Author", 
    from na in this.Authors
    select new XElement("First", na.First)))

上面的块不会像我期望的那样生成XML.我得到的是:

<Authors>
  <Author>
    <First>Steven</First>
    <First>Homer</First>
  </Author>
<Authors>

我希望XML输出看起来像是:

<Authors>
  <Author>
    <First>Steven</First>
    <Last>King</Last>
  </Author>
  <Author>
    <First>Homer</First>
    <Last></Last>
  </Author>
</Authors>

任何有关如何让XML看起来像我需要它的帮助将非常感激!

Answer 1

您需要将IEnumerable<XElement>查询作为第二个参数传递,而不是"作者"字符串,如下所示:

// Note the new way to initialize collections in C# 3.0.
List<Author> authors = new List<Author> ()
{
  new Author { FirstName = "Steven", LastName = "King" }),
  new Author { FirstName = "Homer", LastName = "" })
};

// The XML
XElement xml = new XElement("Authors",
    from na in this.Authors
    select new XElement("Author",
        new XElement("First", na.FirstName),
        new XElement("Last", na.LastName)));

这将为您提供所需的结果.