基于InnerXML对XDocument元素排序

Question

我有一个类似的XML文档:

<document>
    <post>
      <author>Bill Smith</author>
      <subject>Test Article</subject>
      <dates>
          <uploaded>some date</uploaded>
          <published>some date</published>
      </dates>
      <price>
           <provider>Amazon</provider>
           <cost>1540</cost>
      </price>
      <price>
           <provider>WH Smith</provider>
           <cost>2640</cost>
      </price>
    </post>
    <post>
      <author>Bill Smith</author>
      <subject>Test Article</subject>
      <dates>
          <uploaded>some date</uploaded>
          <published>some date</published>
      </dates>
      <price>
           <provider>Amazon</provider>
           <cost>1540</cost>
      </price>
      <price>
           <provider>WH Smith</provider>
           <cost>2640</cost>
      </price>
    </post> 
</document>

我正在使用XDocument w/. net 4.5。我知道我可以用其他方法来排序。

我有它的工作OK拉每个帖子，并把它放到一个帖子模型。但是，我想对价格元素进行排序并挑选出最低的价格(以及供应商)，以便将其插入到我的EF数据库中。

任何帮助将不胜感激，我完全卡住了，甚至从哪里开始这个

Answer 1

你可以试试:

        XDocument doc = XDocument.Load(@"Data.xml");
        var elements = doc.Root
            .Elements("post")
            .Select(post => new
            {
                Author = post.Element("author").Value,
                Subject = post.Element("subject").Value,
                Uploaded = Convert.ToDateTime(post.Element("dates").Element("uploaded").Value),
                Published = Convert.ToDateTime(post.Element("dates").Element("published").Value),
                Price = new
                {
                    P = post
                        .Elements("price")
                        .OrderByDescending(price => Convert.ToDecimal(price.Element("cost").Value))
                        .Select(o => new
                        {
                            Provider = o.Element("provider").Value,
                            Cost = Convert.ToDecimal(o.Element("cost").Value)
                        })
                        .First()
                }
            });
        var p = elements.First();

Answer 2

根据您提供的代码，看看是否有效:

var xmlDocumentElement = xDocument.Load("xmlData.xml").Root;
var posts = xmlDocumentElement.Elements("post").Select(post => new 
    {
    Author = post.Element("author").Value.ToString(),
    Subject = post.Element("subject").Value.ToString(),
    AvailableDate = DateTime.Parse(post.Descendants("dates").FirstOrDefault().Value),
    Price = GetPriceFromPriceXElement(post.Elements("price").Aggregate((prev, next) => 
            Decimal.Parse(prev.Element("cost").Value.ToString()) <= Decimal.Parse(next.Element("cost").Value.ToString()) ? prev : next ))
    }
    );
public Price GetPriceFromPriceXElement(XElement price)
{
   return new Price
    { 
        Provider = price.Element("provider").Value.ToString(),
        Cost = price.Element("cost").Value.ToString()
    };
}

Answer 3

试试这个。这应该行得通。一旦你有了数据，你就可以对它进行按摩。请保管NULL等。这只是关于您的需求的基本想法。

 XDocument doc = XDocument.Load(@"XMLFile1.xml");
        var posts = doc.Root.Elements("post")
                   .Select(p =>
                            new
                            {
                               Author = p.Element("author").Value,
                               Price = p.Elements("price").OrderBy(a => decimal.Parse(a.Element("cost").Value)).First()
                     });
        foreach(var a in posts)
        {
            Console.WriteLine(a.Author + " " + a.Price);
        }

Answer 4

这是一个非常直接的尝试(实际上与Ivan G的答案非常相似):

var posts = from post in document.Root.Elements("post")
            select new
            {
                Author = post.Element("author").Value,
                Subject = post.Element("subject").Value,
                Uploaded = DateTime.Parse(post.Element("dates").Element("uploaded").Value),
                Published = DateTime.Parse(post.Element("dates").Element("published").Value),
                Price = (from price in post.Elements("price")
                         let cost = decimal.Parse(price.Element("cost").Value)
                         orderby cost
                         select new
                         {
                             Provider = price.Element("provider").Value,
                             Cost = cost
                         }).First()
            };

对于你给我们的样本数据(除了日期"某些日期")，它工作得很好。

如果数据可能不完整或错误(即缺失/拼写错误的节点或错误的数据类型)，我建议只取每个XElement而不是值:Author = post.Element("author")等。也许你想允许没有上传或发布日期的帖子。通过这种方式，您可以稍后检查和/或强制转换/转换数据，并可能正确地修复问题。