C# 4.0 使用linq操作XML文档

我需要将以下xml转换为其他形式。我有一个C#代码可以做到这一点，但它有一个很难跟踪的bug。我相信Linq可以提供一种更容易出错的方法。 输入xml:

<NewDataSet>
  <Table>
    <RoleId>5</RoleId>
    <Code>DP</Code>
    <Description>Process data</Description>
    <Task>Validate indices</Task>
    <TaskId>12</TaskId>
    <Country>BE</Country>
    <CountryId>3</CountryId>
  </Table>
  <Table>
    <RoleId>5</RoleId>
    <Code>DP</Code>
    <Description>Process data</Description>
    <Task>calculate indices</Task>
    <TaskId>11</TaskId>
    <Country>US</Country>
    <CountryId>4</CountryId>
  </Table>
  <Table>
    <RoleId>5</RoleId>
    <Code>DP</Code>
    <Description>Process data</Description>
    <Task>Calculate indices</Task>
    <TaskId>11</TaskId>
    <Country>UK</Country>
    <CountryId>5</CountryId>
  </Table>
  <Table>
    <RoleId>1</RoleId>
    <Code>DR</Code>
    <Description>View data</Description>
    <Task>View Reports</Task>
    <TaskId>9</TaskId>
    <Country>SC</Country>
    <CountryId>17</CountryId>
  </Table>
  <Table>
    <RoleId>1</RoleId>
    <Code>DR</Code>
    <Description>View data</Description>
    <Task>View Basics</Task>
    <TaskId>10</TaskId>
    <Country>SC</Country>
    <CountryId>17</CountryId>
  </Table>
  <Table>
    <RoleId>1</RoleId>
    <Code>DR</Code>
    <Description>View data</Description>
    <Task>Download data</Task>
    <TaskId>11</TaskId>
    <Country>FR</Country>
    <CountryId>15</CountryId>
  </Table>
</NewDataSet>

我需要的输出如下：

<NewDataSet>
 <Table>
    <RoleId>5</RoleId>
    <Code>DP</Code>
    <Description>Process data</Description>
    <Task>Validate indices,Calculate indices,</Task>
    <TaskId>12,11</TaskId>
    <Country>BE,US,UK</Country>
    <CountryId>3,4,5</CountryId>
  </Table>
  <Table>
    <RoleId>1</RoleId>
    <Code>DR</Code>
    <Description>Process data from commercial fisheries</Description>
    <Task>View Reports,View Basics,View data</Task>
    <TaskId>9,10,11</TaskId>
    <Country>SC,FR</Country>
    <CountryId>17,15</CountryId>
  </Table>
</NewDataSet>

如您所见，元素按RoleId、Code和Description进行分组

我已经创建了一个custum对象来将xml元素投影到其中

public class Table
{
   public int RoleId {get;set;}
   public string Code  {get;set;}
   public string  Description {get;set;}
   public string Task {get;set;}
   public int TaskId {get;set;}
   public string  Country {get;set;}
   public int CountryId  {get;set;}

}

然后，我们可以使用这个custum对象列表来重新创建一个xml文档。但我在想可能会有一种更为严厉的方式。无需使用custum对象列表

元素的其余部分只是连接在一起。我希望有人对如何使用LINQtoXML实现这一点有一些想法。 非常感谢

var doc = XDocument.Load("Input.txt");

var tables = from t in doc.Root.Elements("Table")
             select new Table
             {
                 RoleId = (int)t.Element("RoleId"),
                 Code = (string)t.Element("Code"),
                 Description = (string)t.Element("Description"),
                 Task = (string)t.Element("Task"),
                 TaskId = (int)t.Element("TaskId"),
                 Country = (string)t.Element("Country"),
                 CountryId = (int)t.Element("CountryId")
             };

var groups = tables.GroupBy(x => new { x.RoleId, x.Code, x.Description });

var resultDoc = new XDocument(
                    new XElement("NewDataSet",
                        from g in groups
                        select new XElement("Table",
                                   new XElement("RoleID", g.Key.RoleId),
                                   new XElement("Code", g.Key.Code),
                                   new XElement("Description", g.Key.Description),
                                   new XElement("Task", string.Join(",", g.Select(x => x.Task))),
                                   new XElement("TaskId", string.Join(",", g.Select(x => x.TaskId.ToString()))),
                                   new XElement("Country", string.Join(",", g.Select(x => x.Country))),
                                   new XElement("CountryId", string.Join(",", g.Select(x => x.CountryId.ToString()))))));

完全是LINQ到XML解决方案，尽管您应该考虑用XML序列化来改变解析部分。 结果XML:

<NewDataSet>
  <Table>
    <RoleID>5</RoleID>
    <Code>DP</Code>
    <Description>Process data</Description>
    <Task>Validate indices,calculate indices,Calculate indices</Task>
    <TaskId>12,11,11</TaskId>
    <Country>BE,US,UK</Country>
    <CountryId>3,4,5</CountryId>
  </Table>
  <Table>
    <RoleID>1</RoleID>
    <Code>Data Reader</Code>
    <Description>View data</Description>
    <Task>View Reports,View Basics,Download data</Task>
    <TaskId>9,10,11</TaskId>
    <Country>SC,SC,FR</Country>
    <CountryId>17,17,15</CountryId>
  </Table>
</NewDataSet>

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你应该在这里展示你的努力：你尝试过的代码，等等。谢谢Marcin，我怎样才能应用disticnt，以便在连接的元素中只返回唯一的值？对不起，我找到了。刚刚在select上再次应用了distinct，非常感谢。