C# h、 Substring（pathElementGroup.Key.Length+1）”因此它将生成一个IEnumerablet这似乎解决了强制转换问题，但如何提取每个id/path？Children=BuildTree（//从propertyPath创建

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h、 Substring（pathElementGroup.Key.Length+1）”因此它将生成一个IEnumerablet这似乎解决了强制转换问题，但如何提取每个id/path？Children=BuildTree（//从propertyPath创建子级（从pathElementGroup中的propertyPathElement，其中propertyPathElement.path.Length>pathElementGroup.Key.Length+1选择new MessageElement（））.ToList（））谢谢你让我试试这个。我会使用IEnumerable，如果这能让事情变得更容易的话。当我开始这项工作时，我试着去做我认为更容易的事情。如果你能向我解释替换为thatLINQ的好处会很好，因为它是基于通用IEnumerable接口的语法糖，请检查这里的详细信息-在我的视图模型中，我正在做这件事测试代码后出现空引用异常。我更新了我的原始帖子。你能看一下吗？…我认为代码中存在问题。其想法是保留分配给每个路径的每个id。例如1，“NetworkControl.AlternateIndexText.Value”或2，“NetworkControl.AddressData.DestinationID”等。

public class MessageElement
{
    private int id;
     public string Name { get; set; }
    public string path { get; set; }
    public List<MessageElement> Children { get; set; }
    public List<MessageElement> messageElements { get; set; }

   public MessageElement()
    {
        Children = new List<MessageElement>();
        messageElements = new List<MessageElement>();
    }

    public MessageElement(int id, string name, List<MessageElement> children)
    {
        this.ID = id;
        this.Name = name;
        this.Children = children;

    }


    public MessageElement(int id, string path)
    {

        this.ID = id;
        this.path = path;

    }
}

   public List<MessageElement> GetRequestTreeNodes()
    {

        messageElements.Add(new MessageElement(1, "NetworkControl.AlternateIndexText.Value"));
        messageElements.Add(new MessageElement(2, "NetworkControl.AddressData.DestinationID"));
        messageElements.Add(new MessageElement(2, "NetworkControl.AddressData.MessageOriginatorID.Value"));


        messageElements.Add(new MessageElement(3, "VehicleSummary.VehicleIdentification.IdentificationID.Value"));
        messageElements.Add(new MessageElement(3, "TitleSummary.JurisdictionTitlingKeyText.Value"));
        messageElements.Add(new MessageElement(1, "VehicleSummary.VehicleIdentification.IdentificationID.Value"));



        return messageElements;

   public List<MessageElement> BuildTree(IEnumerable<MessageElement> messageElements)
    {

        return (
          from element in messageElements           // Ex:(1, "NetworkControl.AlternateIndexText.Value")
          let elementId = element.id                       // get id from message element
          let splitPath = element.path.Split('.')   // get path from  message element
          group element by element.path.Split('.')[0] into pathElementGroup

          select new MessageElement(ID, path)
          {
             ID = elementId,  ??                                 // id of each path  Ex: 1 => "NetworkControl.AlternateIndexText.Value"
              Name = pathElementGroup.Key,             //name of each tree node to be displayed on tree
              Children = BuildTree(                    //create child from the propertyPath
                 (from propertyPathElement in pathElementGroup
                  where propertyPathElement.path.Length > pathElementGroup.Key.Length + 1
                  select new MessageElement())
                 .ToList<MessageElement>())
          }
          );

    }


    }

    BuildTree(                    //create child from the propertyPath
    (from propertyPathElement in pathElementGroup
    where propertyPathElement.path.Length > pathElementGroup.Key.Length + 1
    select propertyPathElement.path.Substring(pathElementGroup.Key.Length + 1)).ToList())
          }

var result = BuildTree(0, GetRequestTreeNodes());

 public List<MessageElement> BuildTree(int depth, List<MessageElement> messageElements)
        {
            if (messageElements == null)
            {
                return null;
            }
            return (
                  from element in BuildGrouping(depth, messageElements)           // Ex:(1, "NetworkControl.AlternateIndexText.Value")
                  let elementId = element.Key                      // get id from message element

                  select new MessageElement()
                  {
                      ID = depth,                                  // id of each path  Ex: 1 => "NetworkControl.AlternateIndexText.Value"
                      Name = element.Key,             //name of each tree node to be displayed on tree
                      Children = BuildTree(depth +1,                    //create child from the propertyPath
                        element.ToList<MessageElement>())
                  }
                  ).ToList<MessageElement>();

        }

        public IEnumerable<IGrouping<string, MessageElement>> BuildGrouping(int depth, List<MessageElement> messageElements)
        {
            string key = string.Empty;
            if (messageElements != null && messageElements.Count > 0)
            {
                string[] splits = messageElements[0].path.Split('.');
                if (splits.Length > depth)
                {
                    key = splits[depth];
                }
            }

            if (string.IsNullOrEmpty(key))
            {
                return new List<IGrouping<string, MessageElement>>();
            }

            return from element in messageElements group element by element.path.Split('.')[depth];
        }