asp.net mvc+EF 递归生成树结构返回json

0、数据表结构，主要属性有：Id、parentId（父节Id）、Text、Url……等等。

1、新建一个树结构MenuModels

    public class MenuModels
     {
         private int _id;
         private string _text;
         private int? _parentid;
         private string _icon;
         private string _url;
         private object _menus;
         private Dictionary<string, string> _attributes = new Dictionary<string, string>();

         public int id
         {
             get { return _id; }
             set { _id = value; }
         }
         public int? parentid
         {
             get { return _parentid; }
             set { _parentid = value; }
         }
         public string text
         {
             get { return _text; }
             set { _text = value; }
         }
         public string icon
         {
             get { return _icon; }
             set { _icon = value; }
         }
         public string url
         {
             get { return _url; }
             set { _url = value; }
         }
         public Dictionary<string, string> attributes
         {
             get { return _attributes; }
             set { _attributes = value; }
         }
         public object menus
         {
             get { return _menus; }
             set { _menus = value; }
         }
     }

2、在控制器中新建如下方法：

 /// <summary>
         /// 加载树
         /// </summary>
         /// <returns></returns>
         public JsonResult LoadTree()
         {
             List<MenuModels> list = InitTree();
             return Json(list, "text/html", JsonRequestBehavior.AllowGet);
         }

  /// <summary>
         /// 初始化树 默认找出顶级菜单
         /// </summary>
         /// <returns></returns>
         public List<MenuModels> InitTree()
         {
             var TreeList = _db.Cent_Tree.ToList();
             List<MenuModels> rootNode = new List<MenuModels>();
             foreach (var plist in TreeList.Where(t => t.ParentID == null))
             {
                 MenuModels jt = new MenuModels();
                 jt.id = plist.ID;
                 jt.text = plist.Name;
                 jt.parentid = plist.ParentID;
                 jt.icon = "";
                 jt.url = plist.SystemUrl;
                 jt.attributes = CreateUrl(TreeList, jt);
                 jt.menus = CreateChildTree(TreeList, jt);
                 rootNode.Add(jt);
             }
             return rootNode;
         }
         /// <summary>
         /// 递归生成子树
         /// </summary>
         /// <param name="TreeList"></param>
         /// <param name="jt"></param>
         /// <returns></returns>
         private List<MenuModels> CreateChildTree(List<Cent_Tree> TreeList, MenuModels jt)
         {
             int keyid = jt.id;//根节点ID
             List<MenuModels> nodeList = new List<MenuModels>();
             var children = TreeList.Where(t => t.ParentID == keyid);
             foreach (var chl in children)
             {
                 MenuModels node = new MenuModels();
                 node.id = chl.ID;
                 node.text = chl.Name;
                 node.parentid = chl.ParentID;
                 node.icon = "";
                 node.url = chl.SystemUrl;
                 node.attributes = CreateUrl(TreeList, node);
                 node.menus = CreateChildTree(TreeList, node);
                 nodeList.Add(node);
             }
             return nodeList;
         }
         /// <summary>
         /// 把Url属性添加到attribute中，如果需要别的属性，也可以在这里添加
         /// </summary>
         /// <param name="TreeList"></param>
         /// <param name="jt"></param>
         /// <returns></returns>
         private Dictionary<string, string> CreateUrl(List<Cent_Tree> TreeList, MenuModels jt)
         {
             Dictionary<string, string> dic = new Dictionary<string, string>();
             int keyid = jt.id;
             var urlList = TreeList.Where(t => t.ID == keyid).SingleOrDefault();
             string Sysurl = urlList.SystemUrl;
             string Indexurl = urlList.IndexUrl;
             dic.Add("sysurl", Sysurl);
             dic.Add("indurl", Indexurl);
             dic.Add("close", "true");
             return dic;
         }

3、运行，http://localhost/Home/loadtree