Introduction

Just follow the following steps in order implement multi-level navigation menu with AngularJS

Here In this article, I have used Visual Studio 2013

Step-1: Create New Project.

Go to File > New > Project > ASP.NET  Web Application (under web) > Entry Application Name > Click OK > Select Empty template > Checked MVC (under "Add folders and core references for" option) > OK

Step-2: Add a Database.

Go to Solution Explorer > Right Click on App_Data folder > Add > New item > Select SQL Server Database Under Data > Enter Database name > Add.

Step-3: Create a table for store menu data.

In this example, I have used 1 table as below, where I have added ParentID column in our table to hold Parent and child relationships between the menus.

Step-4: Add Entity Data Model.

Go to Solution Explorer > Right Click on Project name form Solution Explorer > Add > New item > Select ADO.net Entity Data Model under data > Enter model name > Add.
A popup window will come (Entity Data Model Wizard) > Select Generate from database > Next >
Chose your data connection > select your database > next > Select tables > enter Model Namespace > Finish.

Step-5: Create a javascript file for angular components.

Here I have created a folder named "Scripts" first, and then I have added a javascript file for add angular components (module, controller etc). Here we will fetch menu data from the database.
Right Click on your solution file (from solution explorer) > Add > New Folder > Renamed your folder. and then
Right click on your folder (just created) > Add > New Item > select "javascript" file > Enter name (here "MyApp.js")> Ok.
Write following code

var app = angular.module('MyApp', []);
app.controller('menuController', ['$scope', '$http', function ($scope, $http) {
    $scope.SiteMenu = [];
    $http.get('/home/GetSiteMenu').then(function (data) {
        $scope.SiteMenu = data.data;
    }, function (error) {
        alert('Error');
    })
}])

Step-6: Create a CSS file for styling navigation menu.

Now we will create a CSS file for styling the navigation menu. Here in this example, our menu will be a multi-level menu.
In the same way, first I have added a folder named "css" and then added a CSS file.
Right Click on your solution file (from solution explorer) > Add > New Folder > Renamed your folder. and then
Right click on your folder (just created) > Add > New Item > select "style sheet" file > Enter name (here "navMenu.css") > Ok.
Write following code

/*Here I will write css for show horizantal nav menu*/
ul {
  list-style: none;
  padding: 0;
  margin: 0;
  background: #1bc2a2;
}

ul li {
  display: block;
  position: relative;
  float: left;
  background: #1bc2a2;
}
li ul { display: none; }

ul li a {
  display: block;
  padding: 1em;
  text-decoration: none;
  white-space: nowrap;
  color: #fff;
}

ul li a:hover { background: #2c3e50; }
li:hover > ul {
  display: block;
  position: absolute;
}

li:hover li { float: none; }

li:hover a { background: #1bc2a2; }

li:hover li a:hover { background: #2c3e50; }

.main-navigation li ul li { border-top: 0; }
ul ul ul {
  left: 100%;
  top: 0;
}
ul:before,
ul:after {
  content: " "; /* 1 */
  display: table; /* 2 */
}
ul:after { clear: both; }

Step-7: Create a Controller.

Go to Solution Explorer > Right Click on Controllers folder form Solution Explorer > Add > Controller > Enter Controller name > Select Templete "empty MVC Controller"> Add.

Here I have created a controller named "HomeController"

Step-8: Add new action into your controller for getting the view, where we will show navigation menu

It should be in the Layout page, but I have shown here in the Index page for making the post simple to understand.
Here I have added "Index" Action into "Home" Controller. Please write this following code

public ActionResult Index()
{
    return View();
}

Step-9: Add view for your Action & design for show multi-level navigation menu.

Right Click on Action Method (here right click on Index action) > Add View... > Enter View Name > Select View Engine (Razor) > Add.
HTML Code

@{
    ViewBag.Title = "Index";
}
<h2>Dynamic menu from database in AngularJS</h2>
@* Html code for show nav menu here, for mak the application simple 
    I will add ngapp and ngcontroller here *@
<div ng-app="MyApp">
    <div ng-controller="menuController">
        @* Here first of all we will create a ng-template *@
        <script type="text/ng-template" id="treeMenu">
            <a href="{{menu.Url}}">{{menu.Name}}</a>
            @* We will create submenu only when available *@
            <ul ng-if="(SiteMenu | filter:{ParentID : menu.ID}).length > 0">
                @*<li ng-repeat="menu in SiteMenu | filter:{ParentID : menu.ID}" ng-include="'treeMenu'"></li>*@
                <li ng-repeat="menu in SiteMenu | filter:{ParentID : menu.ID} : true" ng-include="'treeMenu'"></li>
            </ul>
        </script>
        <ul class="main-navigation">
            @* Here we will load only top level menu *@
            @*<li ng-repeat="menu in SiteMenu | filter:{ParentID : 0}" ng-include="'treeMenu'"></li>*@
            <li ng-repeat="menu in SiteMenu | filter:{ParentID : 0} : true" ng-include="'treeMenu'"></li>
        </ul>
    </div>
</div>
@* Add css here for nav menu *@
<link href="~/css/navMenu.css" rel="stylesheet" />

@* add js here for angular app *@
@section Scripts{
    <script src="~/Scripts/MyApp.js"></script>
}

Here you can see, I have used ng-include directive for including templates/HTML fragments.

Step-10: Add an another action into your controller for getting menu data from database

public JsonResult GetSiteMenu()
{
    using (MyDatabaseEntities dc = new MyDatabaseEntities())
    {
        var menu = dc.SiteMenus.ToList();
        return new JsonResult { Data = menu, JsonRequestBehavior = JsonRequestBehavior.AllowGet };
    }
}

Step-11: Modify _Layout.cshtml page for load AngularJS library

_Layout.cshtml HTML Code

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>@ViewBag.Title - My ASP.NET Application</title>
    <link href="~/Content/Site.css" rel="stylesheet" type="text/css" />
    <link href="~/Content/bootstrap.min.css" rel="stylesheet" type="text/css" />
    <script src="~/Scripts/modernizr-2.6.2.js"></script>
</head>
<body>
    <div class="container body-content">
        @RenderBody()
        <hr />
        <footer>
            <p>&copy; @DateTime.Now.Year - My ASP.NET Application</p>
        </footer>
    </div>

    <script src="~/Scripts/jquery-1.10.2.min.js"></script>
    <script src="~/Scripts/bootstrap.min.js"></script>
    <!--HERE we will add angular.js library-->
    <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.4.5/angular.min.js"></script>
    @RenderSection("Scripts", false)
</body>
</html>