This post will walk you through the step-by-step procedure on building a simple ASP.NET 5 application using AngularJS with Web API.

Before we dig further let’s talk about a quick overview of AngularJS and Web API in MVC 6.

Introducing AngularJS

AngularJS is a client-side MVC framework written in JavaScript. It runs in a web browser and greatly helps us (developers) to write modern, single-page, AJAX-style web applications. It is a general purpose framework, but it shines when used to write CRUD (Create Read Update Delete) type web applications.

Introducing Web API

ASP.NET Web API is a framework that makes it easy to build HTTP services that reach a broad range of clients, including browsers and mobile devices. ASP.NET Web API is an ideal platform for building RESTful applications on the .NET Framework. In ASP.NET 5, Web API is now part of MVC 6. Read more here. 

Creating an ASP.NET 5 Project

To start, fire up Visual Studio 2015 and create a new ASP.NET 5 project by selecting File > New Project. In the dialog, under Templates > Visual C#, select ASP.NET Web Application as shown in the figure below: 

Name your project to whatever you like and then click OK. For this example I named the project as “AngularJS101”. Now after that you should be able to see the “New ASP.NET Project” dialog:

Now select ASP.NET 5 Preview Empty template from the dialog above. Then click OK to let Visual Studio generate the necessary files and templates needed for you. You should be able to see something like below:

Adding the Scripts folder

The next thing to do is to create a new folder called “Scripts”. This folder will contain all the JavaScript files needed in our application:

Getting the Required Packages

ASP.NET 5 now supports three main package managers: NuGet, NPM and Bower.

Package Manager

A package manager enables you to easily gather all resources that you need for building an application. In other words you can make use of package manager to automatically download all the resources and their dependencies instead of manually downloading project dependencies such as jQuery, Bootstrap and AngularJS in the web.

NuGet

NuGet manages .NET packages such as Entity Framework, ASP.NET MVC and so on. You typically specify the NuGet packages that your application requires within project.json file.

NPM

NPM is one of the newly supported package manager in ASP.NET 5. This package manager was originally created for managing packages for the open-source NodeJS framework. The package.json is the file that manages your project’s NPM packages.

Bower

Bower is another supported package manager in ASP.NET 5. It was created by Twitter that is designed to support front-end development. You can use Bower to manage client-side resources such as jQuery, AngularJS and Bootstrap.

For this example we need to use NPM to install the resources we need in our application such as Grunt and the Grunt plugins. To do this just right click in your Project (in this case AngularJS101) and select Add > New Item. In the dialog select NPM configuration file as shown in the figure below:

Click Add to generate the file for you. Now open package.json file and modify it by adding the following dependencies:

{
    "version": "1.0.0",
    "name": "AngularJS101",
    "private": true,
    "devDependencies": {
        "grunt": "0.4.5",
        "grunt-contrib-uglify": "0.9.1",
        "grunt-contrib-watch": "0.6.1"
    }
}

Notice that you get Intellisense support while you edit the file. A matching list of NPM package names and versions shows as you type.

In package.json file, from the code above, we have added three (3) dependencies named grunt, grunt-contrib-uglify and grunt-contrib-watch NPM packages that are required in our application.

Now save the package.json file and you should be able to see a new folder under Dependencies named NPM as shown in the following:

Right click on the NPM folder and select Restore Packages to download all the packages required. Note that this may take a bit to finish the download so just be patient and wait ;). After that the grunt, grunt-contrib-uglify and grunt-contrib-watch NPM packages should now be installed as shown in the following:

Configuring Grunt

Grunt is an open-source tool that enables you to build client-side resources for your project. For example, you can use Grunt to compile your LESS or Saas files into CSS. Adding to that, Grunt can also be used to minify CSS and JavaScript files.

In this example, we will use Grunt to combine and minify JavaScript files. We will configure Grunt so that it will take all the JavaScript files from the Scripts folder that we created earlier, combine and minify the files, and finally save the results to a file named app.js within the wwwroot folder.

Now right click on your project and select Add > New Item. Select Grunt Configuration file from the dialog as shown in the figure below:

Then click Add to generate the file and then modify the code within the Gruntfile.js file so it will look like this:

module.exports = function (grunt) { 
    grunt.loadNpmTasks('grunt-contrib-uglify');
    grunt.loadNpmTasks('grunt-contrib-watch');

    grunt.initConfig({
        uglify: {
            my_target: {
                files: { 'wwwroot/app.js': ['Scripts/app.js', 'Scripts/**/*.js'] }
            }
        },

        watch: {
            scripts: {
                files: ['Scripts/**/*.js'],
                tasks: ['uglify']
            }
        }
    });

    grunt.registerTask('default', ['uglify', 'watch']);
};

The code above contains three sections. The first one is used to load each of the Grunt plugins that we need from the NPM packages that we configured earlier. The initConfig() is responsible for configuring the plugins. The Uglify plugin is configured so that it combines and minifies all the files from the Scripts folder and generate the result in a file named app.js within wwwroot folder. The last section contains the definitions for your tasks. In this case we define a single ‘default’ task that runs ‘uglify’ and then watches for changes in our JavaScript file.

Now save the file and let’s run the Grunt file using Visual Studio Task Runner Explorer. To do this, go to View > Other Windows > Task Runner Explorer in Visual Studio main menu. In the Task Runner Explorer make sure to hit the refresh button to load the tasks for our application. You should see something like this:

Now right click on the default task and select Run. You should be able to see the following output:

Configuring ASP.NET MVC

There are two main files that we need to modify to enable MVC in our ASP.NET 5 application.

First, we need to modify the project.json file to in include MVC 6 under dependencies:

    "webroot": "wwwroot",
    "version": "1.0.0-*",
    "dependencies": {
        "Microsoft.AspNet.Server.IIS": "1.0.0-beta3",
        "Microsoft.AspNet.Mvc": "6.0.0-beta3"
    },
    "frameworks": {
        "aspnet50": { },
        "aspnetcore50": { }
    },

Make sure to save the file to restore the packages required. The project.json file is used by the NuGet package manager to determine the packages required in your application. In this case we’ve added Microsoft.AspNet.Mvc.

Now the last thing is to modify the Startup.cs file to add the MVC framework in the application pipeline. Your Startup.cs file should now look like this:

using System; 
using Microsoft.AspNet.Builder; 
using Microsoft.AspNet.Http; 
using Microsoft.Framework.DependencyInjection;

namespace AngularJS101 
{
    public class Startup
    {
        public void ConfigureServices(IServiceCollection services){
            services.AddMvc();
        }

        public void Configure(IApplicationBuilder app){
            app.UseMvc();
        }
    }
}

The ConfigureServices() method is used to register MVC with the ASP.NET 5 built-in Dependency Injection Framework (DI). The Configure() method is used to register MVC with OWIN.

Adding Models

The next step is to create a model that we can use to pass data from the server to the browser/client. Now create a folder named “Models” under the root of your project. Within the “Models” folder, create a class named “DOTAHero” and add the following code below:

using System;

namespace AngularJS101.Models 
{
    public class DOTAHero
    {
        public int ID { get; set; }
        public string Name { get; set; }
        public string Type { get; set; }
    }
}

Create another class called “HeroManager” and add the following code below:

using System.Collections.Generic; 
using System.Linq;

namespace AngularJS101.Models 
{
    public class HeroManager
    {
        readonly List<DOTAHero> _heroes = new List<DOTAHero>() {
            new DOTAHero { ID = 1, Name = "Bristleback", Type="Strength"},
            new DOTAHero { ID = 2, Name ="Abbadon", Type="Strength"},
            new DOTAHero { ID = 3, Name ="Spectre", Type="Agility"},
            new DOTAHero { ID = 4, Name ="Juggernaut", Type="Agility"},
            new DOTAHero { ID = 5, Name ="Lion", Type="Intelligence"},
            new DOTAHero { ID = 6, Name ="Zues", Type="Intelligence"},
            new DOTAHero { ID = 7, Name ="Trent", Type="Strength"},
        };
        public IEnumerable<DOTAHero> GetAll { get { return _heroes; } }

        public List<DOTAHero> GetHeroesByType(string type) {
            return _heroes.Where(o => o.Type.ToLower().Equals(type.ToLower())).ToList();
        }

 public DOTAHero GetHeroByID(int Id) {
            return _heroes.Find(o => o.ID == Id);
        }
    }
}

The HeroManager class contains a readonly property that contains a list of heroes. For simplicity, the data is obviously static. In real scenario you may need to get the data in a storage medium such as database or any files that stores your data. It also contains a GetAll property that returns all the heroes and a GetHeroesByType() method that returns a list of heroes based on the hero type, and finally a GetHeroByID() method that returns a hero based on their ID.

Adding Web API Controller

For this particular example, we will be using Web API for passing data to the browser/client.

Unlike previous versions of ASP.NET, MVC and Web API controllers used the same controller base class. Since Web API is now part of MVC 6 then we can start creating Web API controllers because we already pulled the required NuGet packages for MVC 6 and configured MVC 6 in startup.cs.

Now add an “API” folder under the root of the project:

Then add a Web API controller by right-clicking the API folder and selecting Add > New Item. Select Web API Controller Class and name the controller as “HeroesController” as shown in the figure below:

Click Add to generate the file for you. Now modify your HeroesController class so it will look like this:

using System.Collections.Generic; 
using Microsoft.AspNet.Mvc; 
using AngularJS101.Models;

namespace AngularJS101.API.Controllers 
{
    [Route("api/[controller]")]
    public class HeroesController : Controller
    {
        // GET: api/values
        [HttpGet]
        public IEnumerable<DOTAHero> Get()
        {
            HeroManager HM = new HeroManager();
            return HM.GetAll;
        }

        // GET api/values/7
        [HttpGet("{id}")]
        public DOTAHero Get(int id)
        {
            HeroManager HM = new HeroManager();
            return HM.GetHeroByID(id);
        }

    }
}

At this point we will only be focusing on GET methods to retrieve data. The first GET method returns all the heroes available by calling the GetAll property found in HeroManager class. The second GET method returns a specific hero data based on the ID.

You can test whether the actions are working by running your application in the browser and appending the /api/heroes in the URL. Here are the outputs for both GET actions:

Route: /api/heroes

Route: /api/heroes/7

Creating an AngularJS Application

Visual Studio 2015 includes templates for creating AngularJS modules, controllers, directives and factories. For this example we will be displaying the list of heroes using an AngularJS template.

Adding an AngularJS Module

To get started lets create an AngularJS module by right-clicking on the Scripts folder and selecting Add > New Item. Select AngularJS Module as shown in the figure below.

Click Add to generate the file and copy the following code for our AngularJS module:

(function () {
    'use strict';

    angular.module('heroesApp', [
        'heroesService'      
    ]);
})();

The code above defines a new AngularJS module named “heroesApp”. The heroesApp has a dependency on another AngularJS module named “heroesService” which we will create later in the next step.

Adding an AngularJS Controller

The next thing to do is to create a client-side AngularJS Controller. Create a new folder called “Controllers” under the Script folder as in the following:

 

Click Add and copy the following code below within your heroesController.js file:

(function () {
    'use strict';

    angular
        .module('heroesApp')
        .controller('heroesController', heroesController);

    heroesController.$inject = ['$scope','Heroes'];

    function heroesController($scope, Heroes) {
        $scope.Heroes = Heroes.query();
    }
})();

The code above depends on the Heroes service that supplies the list of heroes. The Heroes service is passed to the controller using dependency injection (DI). The $inject() method call enables DI to work. The Heroes service is passed as the second parameter to the heroesController() function.

Adding the Heroes Service

We will use an AngularJS Heroes service to interact with our data via Web API. Now add a new folder called “Services” within the Script folder. Right click on the Services folder and select Add > New Item. From the dialog select AngularJS Factory and name it as “heroesService.js” as in the following:

Now click Add and then replace the generated default code with the following:

(function () {
    'use strict';

    var heroesService = angular.module('heroesService', ['ngResource']);
    heroesService.factory('Heroes', ['$resource',
        function ($resource) {
            return $resource('/api/heroes', {}, {
                query: { method: 'GET', params: {}, isArray: true}
            });
        }
    ]);
})();

The code above basically returns a list of heroes from the Web API action. The $resource object performs an AJAX request using a RESTful pattern. The heroesService is associated with the /api/heroes route on the server. This means that when you perform a query against the service from your client-side code, the Web API HeroesController is invoked to return a list of heroes.

Adding an AngularJS Template

Let’s add an AngularJS template for displaying the list of heroes. To do this we will need an HTML page to render in the browser. In the wwwroot folder add a new HTML page and name it as “index” for simplicity. Your application structure should now look like this:

The wwwroot folder is a special folder in your application. The purpose is that the wwwroor folder should contain all contents of your website such as HTML files and images needed for your website.

You should not place any of your source code within the wwwroot folder. Instead source codes such as MVC controllers’ source, model classes and unminified JavaScript and LESS files should be placed outside of the wwwroot folder.

Now replace the content of index.html with the following:

<!DOCTYPE html>  
<html ng-app="heroesApp"> 
<head> 
    <meta charset="utf-8" />
    <title>DOTA 2 Heroes</title>
    <script src="//ajax.googleapis.com/ajax/libs/angularjs/1.3.15/angular.js"></script>
    <script src="//ajax.googleapis.com/ajax/libs/angularjs/1.3.15/angular-resource.js"></script>
    <script src="app.js"></script>
</head> 
<body ng-cloak> 
    <div ng-controller="heroesController">
        <h1>DOTA Heroes</h1>
        <table>
            <thead>
                <tr>
                    <th>ID</th>
                    <th>Name</th>
                    <th>Type</th>
                </tr>
            </thead>
            <tbody>
                <tr ng-repeat="hero in Heroes">
                    <td>{{hero.ID}}</td>
                    <td>{{hero.Name}}</td>
                    <td>{{hero.Type}}</td>
                </tr>
            </tbody>
        </table>
    </div>
</body> 
</html> 

There are several things to point out from the markup above: 
The html element is embedded with the ng-app directive. This directive associates the heroesApp with the HTML file.

In the script section, you will notice that I use Google CDN for referencing AngularJS and related libraries. Besides being lazy, it’s my intent to use CDN for referencing standard libraries such as jQuery, AngularJS and Bootstrap to boost application performance. If you don’t want to use CDN then you can always install AngularJS packages using Bower.

The body element is embedded with the ng-cloak directive. This directive hides an AngularJS template until the data has been loaded in the page. 
The div element within the body block is embedded with the ng-controller directive. This directive associates the heroesController and renders the data within the div element.

Finally, the ng-repeat directive is added to the tr element of the table. This will create row for each data that retrieved from the server.

Output

Here’s the output below when running the page and navigating to index.html:

That’s it! It is more fun to play DOTA!

 

There’s a new place to put the app settings for your MVC6 ASP.NET Core application. Web.config is gone but the new solution is great, you get a dependency injected POCO with strongly typed settings instead!

New Settings File - appsettings.json

Instead of web.config, all your settings are now located in appsettings.json. Here’s what the default one looks like, though I’ve also added an AppSettings section:

{
  "AppSettings": {
    "BaseUrls": {
      "API": "https://localhost:44307/",
      "Auth": "https://localhost:44329/",
      "Web": https://localhost:44339/
    },
    "AnalyticsEnabled": true
  },
  "Data": {
    "DefaultConnection": {
      "ConnectionString": "Server=(localdb)\\mssqllocaldb;Database=aspnet5-AppSettings1-ad2c59cc-294a-4e72-bc31-078c88eb3a99;Trusted_Connection=True;MultipleActiveResultSets=true"
    }
  },
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Verbose",
      "System": "Information",
      "Microsoft": "Information"
    }
  }
}

Notice that we’re using JSON instead of XML now. This is pretty great with one big exception, No Intellisense.

Create an AppSettings class

If you’re used to using ConfigurationManager.AppSettings["MySetting"] in your controllers then you’re out of luck, instead you need to setup a class to hold your settings. As you can see above I like to add an “AppSettings” section to the config that maps directly to an AppSettings POCO. You can even nest complex classes as deep as you like:

public class AppSettings
{
    public BaseUrls BaseUrls { get; set; }
    public bool AnalyticsEnabled { get; set; }
}

public class BaseUrls
{
    public string Api { get; set; }
    public string Auth { get; set; }
    public string Web { get; set; }
}  

Configure Startup.cs

Now that we have a class to hold our settings, lets map the data from our appsettings.json. You can do it in a couple of ways

Automatically bind all app settings:

public IServiceProvider ConfigureServices(IServiceCollection services)
{           
    services.Configure<AppSettings>(Configuration.GetSection("AppSettings"));
}

or if you need to alter or transform anything you can assign each property manually:

public IServiceProvider ConfigureServices(IServiceCollection services)
{           
    services.Configure<AppSettings>(appSettings =>
    {
        appSettings.BaseUrls = new BaseUrls()
        {
            // Untyped Syntax - Configuration[""]
            Api = Configuration["AppSettings:BaseUrls:Api"],
            Auth = Configuration["AppSettings:BaseUrls:Auth"],
            Web = Configuration["AppSettings:BaseUrls:Web"],
        };               

        // Typed syntax - Configuration.Get<type>("")
        appSettings.AnalyticsEnabled = Configuration.Get<bool>("AppSettings:AnalyticsEnabled");
    });
}

Using the settings

Finally we can access our settings from within our controllers. We’ll be using dependency injection, so if you’re unfamiliar with that, get ready to learn!

public class HomeController : Controller
{
    private readonly AppSettings _appSettings;

    public HomeController(IOptions<AppSettings> appSettings)
    {
        _appSettings = appSettings.Value;
    }

    public IActionResult Index()
    {
        var webUrl = _appSettings.BaseUrls.Web;

        return View();
    }
}

There are a few important things to note here:

The class we are injecting is of type IOptions<AppSettings>. If you try to inject AppSettings directly it won’t work.

Instead of using the IOptions class throughout the code, instead I set the private variable to just AppSettings and assign it in the constructor using the .Value property of the IOptions class.

By the way, the IOptions class is essentially a singleton. The instance we create during startup is the same throughout the lifetime of the application.

While this is a lot more setup than the old way of doing things, I think it forces developers to code in a cleaner and more modular way.

This is a quick blog post on how to implement bundling and minification in Sitecore MVC project.  During development phase, it is always good to have multiple Javascripts and CSS files for better readability and maintainability of code.  But multiple Javascripts and CSS files degrade the performance of production website and also increase the load time of webpages as it requires multiple HTTP requests from browser to server.  Bundling and minification reduce the size of Javascript and CSS files and bundle multiple files into a single file and make the site perform faster by making fewer HTTP requests. Below steps explain how to implement bundling and minification for Sitecore MVC project: 

1. Add Microsoft ASP.NET Web Optimization Framework to your solution from nuget or run the following command in the Package Manager Console to install Microsoft ASP.NET Web Optimization Framework.

PM> Install-Package Microsoft.AspNet.Web.Optimization

2. Create your CSS and Javascript bundles in “BundleConfig” class under App_Start folder and add reference of "System.Web.Optimization" namespace.

public class BundleConfig
    {
        public static void RegisterBundles(BundleCollection bundles)
        {
            //js bundling using wildcard character *
            bundles.Add(new ScriptBundle("~/bundles/js").Include("~/assets/js/*.js"));

            //css bundling using wildcard character *
            bundles.Add(new StyleBundle("~/bundles/css").Include("~/assets/css/*.css"));
        }
    }

3. Register bundle in the Application_Start method in the Global.asax file. If you are using Multi-site instance of Sitecore MVC then recommend way to implement bundling logic is by creating a new processor into the initialize pipeline. 

protected void Application_Start(object sender, EventArgs e)
        {
            BundleConfig.RegisterBundles(BundleTable.Bundles);
        }

We can override the value of the debug attribute in code by using EnableOptimizations property of the BundleTable class.

protected void Application_BeginRequest(object sender, EventArgs e)
        {
            EnableBundleOptimizations();
        }

        private void EnableBundleOptimizations()
        {
            string debugMode = Request.QueryString["debug"];
            if (!string.IsNullOrEmpty(debugMode) && string.Equals(debugMode, "true", StringComparison.InvariantCultureIgnoreCase))
            {
                BundleTable.EnableOptimizations = false;
            }
            else
            {
                BundleTable.EnableOptimizations = true;
            }
        }

Here in Application_BeginRequest method of Global.asax I am calling one custom method EnableBundleOptimizations() which sets the value of EnableOptimizations property to true or false based on value of querystring “debug”. Main idea behind this logic is that we can check/debug CSS or Javascript file on production by passing querystring parameter debug as true. 

5. Replace Javascripts and CSS references in layout or rendering view with below code:

@Styles.Render("~/bundles/css")
@Styles.Render("~/bundles/js")

6. In web.config set an ignore url prefix for your bundle so that Sitecore won’t try to resolve the URL to the bundle. Update setting IgnoreUrlPrefixes according to your bundle name:

<setting name="IgnoreUrlPrefixes" value="/sitecore/default.aspx|/trace.axd|/webresource.axd|/sitecore/shell/Controls/Rich Text Editor/Telerik.Web.UI.DialogHandler.aspx|/sitecore/shell/applications/content manager/telerik.web.ui.dialoghandler.aspx|/sitecore/shell/Controls/Rich Text Editor/Telerik.Web.UI.SpellCheckHandler.axd|/Telerik.Web.UI.WebResource.axd|/sitecore/admin/upgrade/|/layouts/testing|/bundles/js|/bundles/css"/>

7. Now compile your solution and verify that bundling and minification is enabled by checking view source of webpage.

Pass querystring as debug=true in url and now verify view source of webpage. Bundling and minification is not enabled. This enables us to debug Javascript and CSS files in production website. 

Imagine you have created an MVC project and you are all set to create a session object in order to save your current user Email but after few minutes, you realize that the session object is not working, as it was before.

Oh! Why is it so?

It is because .NET team has created a NuGet package for Session, which is nothing but a very fresh ASP.NET 5 Session State middleware.

OK. So, how to get it?

To install Microsoft.AspNet.Session, run the command, given below, in the Package Manager Console. 

We need to update the startup.cs file, as shown below:

public void ConfigureServices(IServiceCollection services) {  
    // Adds a default in-memory implementation of IDistributedCache  
    services.AddCaching();  
    services.AddSession();  
    //// This Method may contain other code as well  
}  
and in Configure method write below code: public void Configure(IApplicationBuilder app) {  
    app.UseSession();  
    //// This Method may contain other code as well  
}  

How to get and set session?

Let's take some examples.

1. Suppose, you want to use Session in your controller class. For it, you simply have to write Context.Session to access Session.

Set Session syntax:

public IActionResult Index() {  
    ////Context.Session.SetString("First", "I am first!"); ////Before Beta 8  
    HttpContext.Session.SetString("First", "I am first!"); ////From Beta 8 onwards  
    return View();  
}  
Get Session syntax: public IActionResult Index() {  
    ////var myValue = Context.Session.GetString("First"); ////Before Beta 8  
    var myValue = HttpContext.Session.GetString("First"); ////From Beta 8 onwards  
    return View();  
}  

2. Suppose, you want to use Session in a normal class. If you’re not in a Controller, you can still access the HttpContext by injecting IHttpContextAccessor, as shown below:

private readonly IHttpContextAccessor _httpContextAccessor;  
public SessionUtility(IHttpContextAccessor httpContextAccessor) {  
    _httpContextAccessor = httpContextAccessor;  
}  
Set Session syntax: public void SetSession(string key, string value) {  
    HttpContextAccessor.HttpContext.Session.SetString(key, value);  
}  
Get Session syntax: public string GetSession(string key) {  
    return HttpContextAccessor.HttpContext.Session.GetString(key);  
}  
So, whole SessionUtility would be as below: public class SessionUtility {  
    private readonly IHttpContextAccessor HttpContextAccessor;  
    public SessionUtility(IHttpContextAccessor httpContextAccessor) {  
        HttpContextAccessor = httpContextAccessor;  
    }  
    public void SetSession(string key, string value) {  
        HttpContextAccessor.HttpContext.Session.SetString(key, value);  
    }  
    public string GetSession(string key) {  
        return HttpContextAccessor.HttpContext.Session.GetString(key);  
    }  
}  

and it would be registered as:

services.AddTransient<SessionUtility>();  

Here, SessionUtility should be registered only as Transient or Scoped and not Singleton as HttpContext is per-request based.

Please note, I have used it with the key value pair of the string, but you can create the same SessionUtility for the complex scenarios.

Now, suppose you want to check how many times a visitor has visited your site.

For it, you need to add the code, given below, in your startup.cs:

public void Configure(IApplicationBuilder app) {  
    app.UseSession();  
    app.Map("/session", subApp => {  
        subApp.Run(async context => {  
            int visits = 0;  
            visits = context.Session.GetInt32("visits") ? ? 0;  
            context.Session.SetInt32("visits", ++visits);  
            await context.Response.WriteAsync("Counting: You have visited our page this many times: " + visits);  
        });  
    });  
}  

Important!

If you have followed the steps, given above and you still can't get success, you might need a look in your project.json file for the following piece of the code. Well, it should be there.

"frameworks": {  
"dnx451": { },  
"dnxcore50": { } // <-- Remove this if it is in your project.json file.  
},  

Why?

ASP.NET5 Sessions aren’t supported by the DNX Core Runtime.

NuGet package site: https://www.nuget.org/packages/Microsoft.AspNet.Session/

Session is still in its beta versions. Thus, some changes might come, which I will update in this post.

Stay tuned for more updates!

 

Dependency injection (DI) has been possible in previous versions of MVC. With each new version DI has been easier to implement and, with MVC6, DI is supplied right out of the box. In this article we’ll look at how the new DI implementation works, what are its weaknesses and how we can replace it with our favorite DI framework.

What’s new

The unification of APIs across ASP.NET is a common theme throughout ASP.NET 5, and dependency injection is no different. The new ASP.NET stack including: MVC, SignalR and Web API, etc. rely on a built-in minimalistic DI container. The core features of the DI container have been abstracted out to the IServiceProvider interface and are available throughout the stack. Because the IServiceProvider is the same across all components of the ASP.NET framework a single dependency can be resolved from any part of the application.

The DI container supports just 4 modes of operation:

• Instance – a specific instance is given all the time. You are responsible for its initial creation.
• Transient – a new instance is created every time.
• Singleton – a single instance is created and it acts like a singleton.
• Scoped – a single instance is created inside the current scope. It is equivalent to Singleton in the current scope.

BASIC SETUP

Let’s walk through setting up DI in a MVC application. To demonstrate the basics, we’ll resolve the dependency for the service used to get project data. We don’t need to know anything about the service other than that it implements the IProjectService interface, an interface custom to our demo project. IProjectService has one method,GetOrganization(), that method retrieves an organization and its corresponding list of projects.

public interface IProjectService
{
    string Name { get; }
    Organization GetOrganization();
}

public class Organization
{
    public string Name { get; set; }
    [JsonProperty("Avatar_Url")]
    public string AvatarUrl { get; set; }
    public IQueryable<Project> Projects { get; set; }
}

We’ll use the IProjectService to get the organization data and display it in a view. Let’s start by setting up the controller where the service will be used. We’ll use constructor injection by creating a new constructor method for our controller that accepts anIProjectService. Next, the Index action will callGetOrganization, sending the data to the view to be rendered.

private readonly IProjectService projectService;
public HomeController(IProjectService projectService)
{
    this.projectService = projectService;
}
public IActionResult Index()
{
    Organization org = projectService.GetOrganization();
    return View(org);
}

If we try to run the application at this point we’ll receive an exception because we haven’t yet added a concrete implementation of ourIProjectService to the DI container.

InvalidOperationException: Unable to resolve service for type 'DependencyInjectionMVC6Demo. Services. IProjectService' while attempting to activate 'DependencyInjectionMVC6Demo. Controllers. HomeController'.
Microsoft. Framework. DependencyInjection. ActivatorUtilities.GetService(IServiceProvider sp, Type type, Type requiredBy, Boolean isDefaultParameterRequired)

The exception message shows that the code fails during a call toActivatorUtilities.GetService. This is valuable information because it shows that in MVC6 the DI container is already involved in the controller’s construction. Now we just need to tell the container how to resolve the dependency.

In order to resolve the dependency, we need a concrete implementation ofIProjectService. We’ll add a DemoService class and, for simplicity, it will use static dummy data.

public class DemoService : IProjectService
{
    public string Name { get; } = "Demo";

    public Organization GetOrganization() => new Organization
    {
        Name = this.Name,
        AvatarUrl = $"http://placehold.it/100&text={this.Name}",
        Projects = GetProjects()
    };

private IQueryable<Project> GetProjects() => new List<Project> {
         new Project {
             Id = 0,
             Description = "Test project 0",
             Name = "Test 0",
             Stars = 120
         },
         //...
         new Project {
             Id = 4,
             Description = "Test project 4",
             Name = "Test 4",
             Stars = 89
         }
    }.AsQueryable();
}

Finally, we’ll instruct the DI container to instantiate a new DemoServicewhenever IProjectService is required. To configure the container we’ll modify the ConfigureServices method in Startup.cs. Our configuration will be added to the end of this method.

// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
    //... other services
    // Add MVC services to the services container.
    services.AddMvc();

    //our services
}

The service is added by using the AddTransient extension method on the services collection, and setting the IProjectService as the type of service and the DemoService as the implementation.

public void ConfigureServices(IServiceCollection services)
{
    //... other services
    // Add MVC services to the services container.
    services.AddMvc();

    //our services
    services.AddTransient<IProjectService, DemoService>();
}

With the service added, DemoService will now be instantiated when the controller is created, and the exception will no longer be thrown.