请教使用KendoTreeView绑定树，只出root，无ChildNode问题

Question

我是严格按实例操作的，但不知为何，只出顶级菜单，不递归子菜单，搞了一天了，郁闷了
恳请各位帮忙看看问题到底出在那里？
谢谢！运行结果：数据库：
View：
 @(Html.Kendo().TreeView()
 .Name("treeview")
 .DataSource(d => d
        .Model(m => m
            .Id("id")
            .HasChildren("hasChildren")
            .Children("Children"))
        .Read(r => r.Action("TreeResult", "Home")))
    .DataTextField("Name")
    .ExpandAll(true)
    )Controller： public JsonResult TreeResult(int? id)
        {
            TreeTablesRsy treeTablesRsy = new TreeTablesRsy();
            var treeTables = treeTablesRsy.List().Where(m => m.Pid == id || m.Pid == null)
                 .Select(p => new
                 {
                     id = p.TreeId,
                     Name = p.NodeName,
                     hasChildren = p.Items.Any(),
                     Children = p.Items
                 });
            return Json(treeTables, JsonRequestBehavior.AllowGet);
        }Model： public partial class TreeTables
    {
        public TreeTables()
        {
            this.Items = new HashSet<TreeTables>();
        }
        public virtual ICollection<TreeTables> Items { get; set; }
        /// <summary>
        /// id
        /// </summary>         
        [Display(Name = "TreeId")]
        [Key]
        public int TreeId { get; set; }
        /// <summary>
        /// p_id
        /// </summary>         
        [Display(Name = "Pid")]
        public int? Pid { get; set; }  
        /// <summary>
        /// name
        /// </summary>         
        [Display(Name = "NodeName")]
        public string NodeName { get; set; }
    }

Answer 1

无人回答吗？郁闷死了。MVC树型结构难道没有好的方法吗？

Answer 2

ztreehttp://www.ztree.me/v3/api.php

Answer 3

 @(Html.Kendo().TreeView()
 .Name("treeview")
 .DataSource(d => d
        .Read(r => r.Action("TreeResult", "Home")))
    .DataTextField("Name")
    )
 public JsonResult TreeResult(int? id)
        {
            TreeTablesRsy treeTablesRsy = new TreeTablesRsy();
            var treeTables = treeTablesRsy.List().Where(m => m.Pid == id)
                 .Select(p => new
                 {
                     id = p.TreeId,
                     Name = p.NodeName,
                     hasChildren = treeTablesRsy.List().Any(x => x.Pid == p.TreeId),
                     expanded = true
                 });
            return Json(treeTables, JsonRequestBehavior.AllowGet);
        }
 public partial class TreeTables
    {
        /// <summary>
        /// id
        /// </summary>         
        [Display(Name = "TreeId")]
        [Key]
        public int TreeId { get; set; }
        /// <summary>
        /// p_id
        /// </summary>         
        [Display(Name = "Pid")]
        public int? Pid { get; set; }  
        /// <summary>
        /// name
        /// </summary>         
        [Display(Name = "NodeName")]
        public string NodeName { get; set; }
    }