linq-to-xml - LINQ to XML GroupBy

Question

我想使用 LINQ 通过在“摘要”字段上执行 GROUPBY 并将余额字段求和来将输入 XML 转换为输出 XML。

输入 XML:

<Root>
  <Account>
    <Summary>Checking</Summary>
    <Comprehensive>Interest Checking Account</Comprehensive>
    <Currency>Dollar</Currency>
    <Balance>10000000.000000</Balance>
  </Account>
  <Account>
    <Summary>Savings</Summary>
    <Comprehensive>Market Account</Comprehensive>
    <Currency>Dollar</Currency>
    <Balance>20000000.000000</Balance>
  </Account>
  <Account>
    <Summary>Checking</Summary>
    <Comprehensive>Interest Checking Account</Comprehensive>
    <Currency>Dollar</Currency>
    <Balance>50000000.000000</Balance>
  </Account>  
</Root>

输出 XML:

<Root>
  <Account>
    <Summary>Checking</Summary>
    <Comprehensive>Interest Checking Account</Comprehensive>
    <Currency>Dollar</Currency>
    <Balance>60000000.000000</Balance>
  </Account>
  <Account>
    <Summary>Savings</Summary>
    <Comprehensive>Market Account</Comprehensive>
    <Currency>Dollar</Currency>
    <Balance>20000000.000000</Balance>
  </Account>
</Root>

我试过这个，但无法获得节点/元素:

XElement groupData = new XElement("Root",
    chartData.Elements().GroupBy(x => x.Element("Summary").Value).
        Select(g => new XElement("Account", g.Key, g.Elements("Comprehensive"),
            g.Elements("Currency"),
            g.Sum(
                s =>
                (decimal)
                s.Element("Balance")))));

任何帮助，将不胜感激。提前致谢。

Answer 1

如果您不想要中间对象，您可以使用

    XDocument input = XDocument.Load("input.xml");
    XDocument output =
        new XDocument(
            new XElement(input.Root.Name,
                from account in input.Root.Elements("Account")
                group account by account.Element("Summary").Value into g
                select new XElement("Account",
                    g.ElementAt(0).Elements().Where(e => e.Name != "Balance"),
                    new XElement("Balance", g.Elements("Balance").Sum(b => (decimal)b)
                    ))));
    output.Save("output.xml");

或者你可以使用方法语法

    XDocument input = XDocument.Load(@"input.xml");
    XDocument output = new XDocument(
            new XElement(input.Root.Name,
                input.Root.Elements("Account")
                .GroupBy(a => a.Element("Summary").Value)
                .Select(g => new XElement("Account",
                    g.ElementAt(0).Elements().Where(e => e.Name != "Balance"),
                    new XElement("Balance", g.Elements("Balance").Sum(b => (decimal)b)
                    )))));
    output.Save("output.xml");