Windows 2012 Hosting - MVC 6 and SQL 2014 BLOG

Tutorial and Articles about Windows Hosting, SQL Hosting, MVC Hosting, and Silverlight Hosting

ASP.NET MVC Hosting - ASPHostPortal.com :: Simple Way to Upload File in ASP.NET MVC 4.0 Razor

clock October 19, 2015 19:00 by author Dan

In this tutorial I will show you how to upload a files in ASP.NET MVC 4.0. So how to do this?? Lets get start. Create a new MVC 4.0 application and add a new controller, name it as HomeController. We will use Index ActionMethod to write the code to upload the file.

We need two ActionMethod named Index, one is for HttpGet and another for HttpPost. Within the HttpGet ActionMethod we don't need to write anything.

Lets create the View first. To create the View right click on the ActionMethod Index and click on the Add View option.

In the View write down the code.

@{
    ViewBag.Title = "Upload file";
}

<h2>Upload File</h2>
<h3 style="color: green">@ViewBag.Message</h3>
@using (Html.BeginForm("Index", "Home", FormMethod.Post
            , new { enctype = "multipart/form-data" }))
{
    @Html.ValidationSummary();

    <input type="file" id="fileToUpload" name="file" />
    <span class="field-validation-error" id="spanfile"></span>

    <input type="submit" id="btnSubmit" value="Upload" />
}


Here we have taken a simple HTML file up loader and a submit button. Within the form we are calling the ActionMethod Index, which is present in HomeController. A ValidationSummary to show all validation message.

Now get back to the ActionMethod. Within the Index ActionMethod (HttpPost) write down the code.

[HttpPost]
public ActionResult Index(HttpPostedFileBase file)
{
      if (ModelState.IsValid)
      {
           if (file == null)
           {
              ModelState.AddModelError("File", "Please Upload Your file");
           }
           else if (file.ContentLength > 0)
           {
              int MaxContentLength = 1024 * 1024 * 4; //Size = 4 MB
              string[] AllowedFileExtensions = new string[] { ".jpg", ".gif", ".png", ".pdf" };
           if (!AllowedFileExtensions.Contains
(file.FileName.Substring(file.FileName.LastIndexOf('.'))))
           {
                 ModelState.AddModelError("File", "Please file of type: " + string.Join(", ", AllowedFileExtensions));
           }
           else if (file.ContentLength > MaxContentLength)
           {
                 ModelState.AddModelError("File", "Your file is too large, maximum allowed size is: " + MaxContentLength + " MB");
            }
            else
            {
                 var fileName = Path.GetFileName(file.FileName);
                 var path = Path.Combine(Server.MapPath("~/Upload"), fileName);
                 file.SaveAs(path);
                 ModelState.Clear();
                 ViewBag.Message = "File uploaded successfully. File path :   ~/Upload/"+fileName;
             }
         }
     }
     return View();
}


Before run this project don't forget to create a Upload folder within root directory, otherwise you will get an error.

HttpPostedFileBase file getting the file which you are uploading.

file.ContentLength : Size of the file
file.FileName : file name with extension

Now run your project and enjoying your uploading.

Best Windows Shared Hosting Recommendation

ASPHostPortal.com provides our customers with Plesk Panel, one of the most popular and stable control panels for Windows hosting, as free. You could also see the latest .NET framework, a crazy amount of functionality as well as Large disk space, bandwidth, MSSQL databases and more. All those give people the convenience to build up a powerful site in Our Shared Hosting. We offers Windows hosting starts from $5/month only. We also guarantees 30 days money back and guarantee 99.9% uptime. If you need a reliable affordable Windows Shared Hosting, we should be your best choice.



ASP.NET Hosting - ASPHostPortal.com : Dynamically Create Meta Description Using ASP.NET

clock October 13, 2015 08:37 by author Kenny

Dynamically Create Meta Description Using ASP.NET

HTML “meta description” allows us to describe web pages with short and sometimes elaborated details. Descriptions written inside the <meta> tag, must always to specific and are often limited to very few characters. Using Asp.Net, we can easily create “meta” descriptions dynamically, through code behind procedures, describing the contents of the page.

We all know how important it is to use meta tags when you’re building an internet web site. Meta tags provide metadata about the HTML document. They are not rendered in the browser but are used by search engines to parse web pages. The following article demonstrates how to store meta tags for each page in an XML file and how to use LINQ to read the XML data and dynamically create meta tags for each page in your website.

Open Visual Studio 2008 and choose File > New > Web > ASP.NET Web Application.

Add a Master Page to the project. Once that is completed, add a Web Content Page and select the newly created Master Page as the Master Page.

The next step is to create a new folder in the web site to demonstrate all pages in the website will have dynamic meta tags at runtime. Right click the website and choose Add > New Folder. Name the new folder ChildFolder. After this add a new Web Content Page to this folder. Leave the default name as this is not important.

Now that we have two pages in different folders, it’s now time to create an XML file that contains the data for the meta tags. Right click the website and choose Add > New Item > XML File. Name the file TagData.xml and add the following XML:

<metaTags>
 <tags pageName="/WebForm1.aspx">
    <tag name="keyword" value="This is a keyword"></tag>
    <tag name="description" value="This is a description"></tag>
    <tag name="author" value="malcolm sheridan"></tag>
 </tags>
 <tags pageName="/ChildFolder/WebForm1.aspx">
    <tag name="keyword" value="This is a keyword for the child pages"></tag>
    <tag name="description" value="This is a description for the child pages"></tag>
    <tag name="author" value="malcolm sheridan for this page too"></tag>
 </tags>
</metaTags>

In the XML above I have created a parent node called metaTags. Inside I have created a tags node which contains a pageName attribute. That value is how we will match the current requested page to the XML data. Each tags node contains a tag node that corresponds to the meta data we want sent to the browser. In this example I want to set meta tags for the all the pages to have keyword, description and author meta tags, but the values rendered to the browser will differ depending on what page the user is on. In a real world scenario this information would be stored inside a database, but I decided to keep this data inside an XML file to keep it simple and focus on how to do this.

Having outlined what meta tags we want sent to the browser, we now have to write the code that will read the XML file and dynamically add the meta tags at runtime. Seeing as though we’re using Master Pages this is the ideal spot to add it. Add the following code to read the XML file:

C#

XDocument doc = XDocument.Load(Server.MapPath("~/TagData.xml"));
var metaTags = doc.Descendants("tag")
              .Where(o => o.Parent.Attribute("pageName").Value == Request.Url.AbsolutePath)
               .Select(o => new
               {
                    Value = o.Attribute("value").Value,
                    Name = o.Attribute("name").Value
               });

VB.NET

Dim doc As XDocument = XDocument.Load(Server.MapPath("~/TagData.xml"))
Dim metaTags = doc.Descendants("tag").Where(Function(o) o.Parent.Attribute("pageName").Value = Request.Url.AbsolutePath).Select(Function(o) New With {Key .Value = o.Attribute("value").Value, Key .Name = o.Attribute("name").Value})

For flexibility and ease of use I have decided to use the power of LINQ to XML to read the XML data. To start with the XML document is load into an XDocument object. From there I have created a LINQ query to return all the tag nodes where the parent node has an attribute called pageName and the value is equal to the current page.   Then the object returned is an anonymous type that has a Value and Name property. The values of those properties are the value and name attribute values.

Now that we have the data in memory, the next step is to create the meta tag and add it to the page dynamically. To do this you use the HtmlMeta class. This allows you programmatic access to the HTML meta tags. Add the following code below to your project:

C#

foreach (var item in metaTags)
{              
     HtmlMeta meta = new HtmlMeta();
     meta.Name = item.Name;
     meta.Content = item.Value;
     Page.Header.Controls.Add(meta);
}

VB.NET

For Each item In metaTags
       Dim meta As New HtmlMeta()
       meta.Name = item.Name
       meta.Content = item.Value
       Page.Header.Controls.Add(meta)
Next item

The foreach loop enumerates through each item returned from the LINQ query. It assigns the Name and Content value to the HtmlMeta object. Finally the object is added to the page by calling Page.Header.Controls.Add(meta). Run the project and once the default page has loaded, view the HTML source and you’ll see the meta tags have been added to the website.

MetaTags

Browsing to the second page and viewing the HTML source, you’ll find the meta tags have been added to the page but they’re different values from the previous page.

Best Windows Shared Hosting Recommendation

ASPHostPortal.com provides our customers with Plesk Panel, one of the most popular and stable control panels for Windows hosting, as free. You could also see the latest .NET framework, a crazy amount of functionality as well as Large disk space, bandwidth, MSSQL databases and more. All those give people the convenience to build up a powerful site in Our Shared Hosting. We offers Windows hosting starts from $5/month only. We also guarantees 30 days money back and guarantee 99.9% uptime. If you need a reliable affordable Windows Shared Hosting, we should be your best choice.



ASP.NET 5 Hosting - ASPHostPortal :: How To Configuration in ASP.NET 5

clock September 21, 2015 11:33 by author Kenny

How To Configuration in ASP.NET 5

Goodbye XML, Hello JSON

In the past, ASP.NET has been built on a foundation of XML. Web Forms .aspx and .ascx files are basically XML files and configuration in previous versions of ASP.NET is managed in an XML file called web.config. The web.config file has a particular structure and a class (System.Web.Configuration.WebConfigurationManager) devoted to providing access to it. In ASP.NET 5 JSON is the preferred format for storing structured information such as configuration. This change has largely been driven, I suspect, by the desire to appeal to web developers working on other platforms who are more used to JSON as a structured data format. The first article in this series has already looked at the new JSON solution and project files: global.json and project.json.

The default replacement for the web.config file is config.json. You can also choose to use an XML file if you prefer, and INI files, environment variables, command line arguments and an in-memory option are supported natively too. The template for a config.json file is labelled as ASP.NET Configuration File in the Add New Item dialog:

When you add one, the templated content provides a placeholder for a connection string:

{
    "Data": {
        "DefaultConnection": {
            "ConnectionString": "Server=(localdb)\\MSSQLLocalDB;Database=_CHANGE_ME;Trusted_Connection=True;"
        }
    }
}

Strongly Typed AppSettings

In earlier versions of ASP.NET, it is quite common to store application-wide constants in the appSettings section of a web.config file. You can store these values in the config.json file instead. Previous Beta release templates included an example of this, but it has been removed from the Beta 6 template. The steps described below demonstrate how to use the config.json file to store appsettings and how to provide strongly-typed access to them.

Add the highlighted code to the config.json file:

{
    "AppSettings" : {
        "SiteTitle" :  "My Web Site"
    },
    "Data": {
        "DefaultConnection": {
            "ConnectionString": "Server=(localdb)\\MSSQLLocalDB;Database=_CHANGE_ME;Trusted_Connection=True;"
        }
    }
}

Right click on the Properties node in Solution Explorer (depicted by a wrench icon) and select Add » New Item.

Add a C# class file named AppSettings.cs and replace its default content with the following:

namespace WebApplication2
{
    public class AppSettings
    {
        public string SiteTitle { get; set; }
    }
}

Change the dependencies section in project.json to include the highlighted lines below

  "dependencies": {
    "Microsoft.AspNet.Server.IIS": "1.0.0-beta6",
    "Microsoft.AspNet.Server.WebListener": "1.0.0-beta6",
    "Microsoft.AspNet.Mvc": "6.0.0-beta6",
    "Microsoft.Framework.Configuration.Json": "1.0.0-beta6"
  },

Make the following highlighted changes to Startup.cs:

using Microsoft.AspNet.Builder;
using Microsoft.AspNet.Hosting;
using Microsoft.AspNet.Http;
using Microsoft.Framework.Configuration;
using Microsoft.Framework.DependencyInjection;
using Microsoft.Framework.OptionsModel;
using Microsoft.Framework.Runtime;

namespace WebApplication2
{
    public class Startup
    {
        public IConfiguration Configuration { get; set; }

        public Startup(IHostingEnvironment env, IApplicationEnvironment appEnv)
        {
            var builder = new ConfigurationBuilder(appEnv.ApplicationBasePath)
                .AddJsonFile("config.json");
            Configuration = builder.Build();
        }
        public void ConfigureServices(IServiceCollection services)
        {
            services.Configure<AppSettings>(Configuration.GetConfigurationSection("AppSettings"));
            services.AddMvc();
        }

        public void Configure(IApplicationBuilder app)
        {
            var appSettings = app.ApplicationServices.GetService<IOptions<AppSettings>>();
            app.Run(async (context) =>
            {
                await context.Response.WriteAsync(appSettings.Options.SiteTitle);
            });
        }
    }
}

Press Ctrl+F5 to run the application without debugging. You should see "My Web Site" written to the browser.

You started by adding a new section called AppSettings to the config.json file and declaring a property with a value. Then you created a C# class called AppSettings with one property that matches the one you added to the config file. The AppSettings class is designed to provide strongly typed access to the appSettings section of the config.json file. You added a couple of packages to the project.json file to make them available to the application. The first package enables you to use JSON as the format for your configuration data. The second package introduces MVC into the application.

In the Startup class, you added a constructor where you instantiated a variable representing the project's configuration as the config.json file and assigned that to a property that you created of type IConfiguration. This holds the values loaded from the configuration source (the config.json file). You made the AppSettings available to the application by registering it with the dependency injection system in the ConfigureServices method. The method you used mapped the json values from the configuration file to the AppSettings class. You also registered the MVC framework with the dependency injection system. Finally, you used the GetService<T> extension method to retrieve the AppSettings from the DI system in the Startup class'sConfigure method where you used them to write the SiteTitle value to the browser.

Best Windows Shared Hosting Recommendation

ASPHostPortal.com provides our customers with Plesk Panel, one of the most popular and stable control panels for Windows hosting, as free. You could also see the latest .NET framework, a crazy amount of functionality as well as Large disk space, bandwidth, MSSQL databases and more. All those give people the convenience to build up a powerful site in Our Shared Hosting. We offers Windows hosting starts from $5/month only. We also guarantees 30 days money back and guarantee 99.9% uptime. If you need a reliable affordable Windows Shared Hosting, we should be your best choice.



Entity Framework 7 Hosting - ASPHostPortal :: Introduction Entity Framework 7, ASP.NET 5 and ASP.NET MVC 6

clock August 20, 2015 08:44 by author Jervis

Introduction ASP.NET 5 MVC 6 Web API and Entity Framework 7

In this post, we will only show simple example using ASP.NET 5 and new Entity Framework 7. We will cover about:

- Using the ASP.NET 5 empty template to build the Web API from scratch.
- Overview of the new project structure in VS 2015 and how to use the new dependency management tool.
- Configuring ASP.NET 5 pipeline to add only the components needed for our Web API.
- Using EF 7 commands and the K Version Manager (KVM) to initialize and apply DB migrations.

First – Create an Empty Project

Open your Visual Studio 2015 and create new project named “Registration_MVC6WebApi”

Then, select template named “ASP.NET 5 Empty”

Second Step – Adding the Dependencies

Once you have created this project, you will see there is file named “project.json” and this file contains all your project settings along with a section for managing project dependencies on other frameworks/components.

We’ve used to manage packages/dependencies by using NuGet package manager, and you can do this with the new enhanced NuGet package manager tool which ships with VS 2015, but in our case we’ll add all the dependencies using the “project.json” file and benefit from the IntelliSense provided as the image below:

So we will add the dependencies needed to configure our Web API, so open file “project.json” and replace the section “dependencies” with the section below:

"dependencies": {
        "Microsoft.AspNet.Server.IIS": "1.0.0-beta1",
        "EntityFramework": "7.0.0-beta1",
        "EntityFramework.SqlServer": "7.0.0-beta1",
        "EntityFramework.Commands": "7.0.0-beta1",
        "Microsoft.AspNet.Mvc": "6.0.0-beta1",
        "Microsoft.AspNet.Diagnostics": "1.0.0-beta1",
        "Microsoft.Framework.ConfigurationModel.Json": "1.0.0-beta1"
    }

The use for each dependency we’ve added as the below:

  • Microsoft.AspNet.Server.IIS: We want to host our Web API using IIS, so this package is needed. If you are planning to self-host your Web API then no need to add this package.
  • EntityFramework & EntityFramework.SqlServer: Our data provider for the Web API will be SQL Server. Entity Framework 7 can be configured to work with different data providers and not only relational databases, the data providers supported by EF 7 are: SqlServer, SQLite, AzureTableStorage, and InMemory. More about EF 7 data providers here.
  • EntityFramework.Commands: This package will be used to make the DB migrations command available in our Web API project by using KVM, more about this later in the post.
  • Microsoft.AspNet.Mvc: This is the core package which adds all the needed components to run Web API and MVC.
  • Microsoft.AspNet.Diagnostics: Basically this package will be used to display a nice welcome page when you request the base URI for the API in a browser. You can ignore this if you want, but it will be nice to display welcoming page instead of the 403 page displayed for older Web API 2.
  • Microsoft.Framework.ConfigurationModel.Json: This package is responsible to load and read the configuration file named “config.json”. We’ll add this file in a later step. This file is responsible to setup the “IConfiguration” object. 

Last thing we need to add to the file “project.json” is a section named “commands” as the snippet below:

"commands": {
        "ef": "EntityFramework.Commands"
}

We’ve added short prefix “ef” for EntityFramework.Commands which will allow us to write EF commands such as initializing and applying DB migrations using KVM.

Third Step - Adding config.json configuration file

Now right click on your project and add new item of type “ASP.NET Configuration File” and name it “config.json”, you can think of this file as a replacement for the legacy Web.config file, for now this file will contain only our connection string to our SQL DB, I’m using SQL Express here and you can change this to your preferred SQL server.

{
    "Data": {
        "DefaultConnection": {
            "Connectionstring": "Data Source=.\\sqlexpress;Initial Catalog=RegistrationDB;Integrated Security=True;"
        }
    }
}

Step no. 4 – Configure ASP.NET 5 Pipeline

This is the class which is responsible for adding the components needed in our pipeline, currently with the ASP.NET 5 empty template, the class is empty and our web project literally does nothing, I’ll add all the code in our Startup class at once then describe what each line of code is responsible for, so open file Startup.cs and paste the code below:

using System;
using Microsoft.AspNet.Builder;
using Microsoft.AspNet.Http;
using Microsoft.AspNet.Hosting;
using Microsoft.Framework.ConfigurationModel;
using Microsoft.Framework.DependencyInjection;
using Registration_MVC6WebApi.Models;

namespace Registration_MVC6WebApi
{
    public class Startup
    {
        public static IConfiguration Configuration { get; set; }

        public Startup(IHostingEnvironment env)
        {
            // Setup configuration sources.
            Configuration = new Configuration().AddJsonFile("config.json").AddEnvironmentVariables();
        }
        public void ConfigureServices(IServiceCollection services)
        {
            // Add EF services to the services container.
            services.AddEntityFramework().AddSqlServer().AddDbContext<RegistrationDbContext>();

            services.AddMvc();

            //Resolve dependency injection
            services.AddScoped<IRegistrationRepo, RegistrationRepo>();
            services.AddScoped<RegistrationDbContext, RegistrationDbContext>();
        }
        public void Configure(IApplicationBuilder app)
        {
            // For more information on how to configure your application, visit http://go.microsoft.com/fwlink/?LinkID=398940
            app.UseMvc();

            app.UseWelcomePage();

        }
    }
}

Step 5 – Adding Models, Database Context, and Repository

Now we’ll add a file named “Course” which contains two classes: “Course” and “CourseStatusModel”, those classes will represents our domain data model, so for better code organizing add new folder named “Models” then add the new file containing the the code below:

using System;
using System.ComponentModel.DataAnnotations;

namespace Registration_MVC6WebApi.Models
{
    public class Course
    {
        public int Id { get; set; }
        [Required]
        [StringLength(100, MinimumLength = 5)]
        public string Name { get; set; }
        public int Credits { get; set; }
    }

    public class CourseStatusModel
    {
        public int Id { get; set; }
        public string Description { get; set; }
    }
}

Now we need to add Database context class which will be responsible to communicate with our database, so add new class and name it “RegistrationDbContext” then paste the code snippet below:

using Microsoft.Data.Entity;
using System;
using Microsoft.Data.Entity.Metadata;

namespace Registration_MVC6WebApi.Models
{
    public class RegistrationDbContext :DbContext
    {
        public DbSet<Course> Courses { get; set; }

        protected override void OnConfiguring(DbContextOptions options)
        {
            options.UseSqlServer(Startup.Configuration.Get("Data:DefaultConnection:ConnectionString"));
        }
    }
}

Basically what we’ve implemented here is adding our Courses data model as DbSet so it will represent a database table once we run the migrations, note that there is a new method named “OnConfiguration” where we can override it so we’ll be able to specify the data provider which needs to work with our DB context.

In our case we’ll use SQL Server, the constructor for “UseSqlServer” extension method accepts a parameter of type connection string, so we’ll read it from our “config.json” file by specifying the key “Data:DefaultConnection:ConnectionString” for the “Configuration” object we’ve created earlier in Startup class.

Lastly we need to add the interface “IRegistrationRepo” and the implementation for this interface “RegistrationRepo”, so add two new files under “Models” folder named “IRegistrationRepo” and “RegistrationRepo” and paste the two code snippets below:

IRegistrationRepo Code

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

namespace Registration_MVC6WebApi.Models
{
    public interface IRegistrationRepo
    {
        IEnumerable<Course> GetCourses();
        Course GetCourse(int courseId);
        Course AddCourse(Course course);
        bool DeleteCourse(int courseId);
    }
}

RegistrationRepo implementation

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


namespace Registration_MVC6WebApi.Models
{
    public class RegistrationRepo : IRegistrationRepo
    {
        private readonly RegistrationDbContext _db;

        public RegistrationRepo(RegistrationDbContext db)
        {
            _db = db;
        }
        public Course AddCourse(Course course)
        {
            _db.Courses.Add(course);

            if (_db.SaveChanges() > 0)
            {
                return course;
            }
            return null;

        }

        public bool DeleteCourse(int courseId)
        {
            var course = _db.Courses.FirstOrDefault(c => c.Id == courseId);
            if (course != null)
            {
                _db.Courses.Remove(course);
                return _db.SaveChanges() > 0;
            }
            return false;
        }

        public Course GetCourse(int courseId)
        {
            return _db.Courses.FirstOrDefault(c => c.Id == courseId);
        }

        public IEnumerable<Course> GetCourses()
        {
            return _db.Courses.AsEnumerable();
        }
    }
}

The implementation here is fairly simple, what worth noting here is how we’ve passed “RegistrationDbContext” as parameter for our “RegistrationRepo” constructor so we’ve implementedConstructor Injection, this will not work if we didn’t configure this earlier in our “Startup” class.

Step 6 - Installing KVM (K Version Manager)

After we’ve added our Database context and our domain data models, we can use migrations to create the database, with previous version of ASP.NET we’ve used NuGet package manager for these type of tasks, but with ASP.NET 5 we can use command prompt using various K* commands.

What is KVM (K Version Manager)?  KVM is a Powershell script used to get the runtime and manage multiple versions of it being on the machine at the same time, you can read more about it here.

Now to install KVM for the first time you have to do the following steps:

1. Open a command prompt with Run as administrator.
2. Run the following command:

@powershell -NoProfile -ExecutionPolicy unrestricted -Command "iex ((new-object net.webclient).DownloadString('https://raw.githubusercontent.com/aspnet/Home/master/kvminstall.ps1'))"

3. The script installs KVM for the current user.
4. Exit the command prompt window and start another as an administrator (you need to start a new command prompt to get the updated path environment).
5. Upgrade KVM with the following command:

KVM upgrade

Next Step - Initializing and applying migrations Database

Now our command prompt is ready to understand K commands and Entity Framework commands, first step to do is to change the directory to the project directory. The project directory contains the “project.json” file as the image below:

So in the command prompt we need to run the 2 following commands:

k ef migration add initial
k ef migration apply

Basically the first command will add migration file with the name format (<date>_<migration name>) so we’ll end up having file named “201411172303154_initial.cs” under folder named “Migrations” in our project. This auto generated file contains the code needed to to add our Courses table to our database, the newly generated files will show up under your project as the image below:

The second command will apply those migrations and create the database for us based on the connection string we’ve specified earlier in file “config.json”.

Note: the “ef” command comes from the settings that we’ve specified earlier in file “project.json” under section “commands”.

Step 8 - Adding GET methods for Courses Controller

The controller is a class which is responsible to handle HTTP requests, with ASP.NET 5 our Web API controller will inherit from “Controller” class not anymore from “ApiController”, so add new folder named “Controllers” then add new controller named “CoursesController” and paste the code below:

using Microsoft.AspNet.Mvc;
using Registration_MVC6WebApi.Models;
using System;
using System.Collections.Generic;

namespace Registration_MVC6WebApi.Controllers
{
    [Route("api/[controller]")]
    public class CoursesController : Controller
    {
        private IRegistrationRepo _registrationRepo;

        public CoursesController(IRegistrationRepo registrationRepo)
        {
            _registrationRepo = registrationRepo;
        }

        [HttpGet]
        public IEnumerable<Course> GetAllCourses()
        {
            return _registrationRepo.GetCourses();
        }

        [HttpGet("{courseId:int}", Name = "GetCourseById")]
        public IActionResult GetCourseById(int courseId)
        {
            var course = _registrationRepo.GetCourse(courseId);
            if (course == null)
            {
                return HttpNotFound();
            }

            return new ObjectResult(course);
        }

    }
}

What we’ve implemented in the controller class is the following:

1. The controller is attribute with Route attribute as the following [Route("api/[controller]")] so any HTTP requests that match the template are routed to the controller. The “[controller]” part in the template URL means to substitute the controller class name, minus the “Controller” suffix. In our case and for “CoursesController” class, the route template is “api/courses”.

2. We’ve defined two HTTP GET methods, the first one “GetAllCourses” is attributed with “[HttpGet]” and it returns a .NET object which is serialized in the body of the response using the default JSON format.

3. The second HTTP GET method “GetCourseById” is attributed with “[HttpGet]“. For this method we’ve specified a constraint on the parameter “courseId”, the parameter should be of integer data type. As well we’ve specified a name for this method “GetCourseById” which we’ll use in the next step. Last thing this method returns object of type IActionResult which gives us flexibility to return different actions results based on our logic, in our case we will return HttpNotFound if the course does not exist or we can return serialized JSON object of the course when the course is found.

4. Lastly notice how we are passing the “IRegistrationRepo” as a constructor for our CoursesController, by doing this we are implementing Constructor Injection.

Last Step - Adding POST and DELETE methods for Courses Controller

Now we want to implement another two HTTP methods which allow us to add new Course or delete existing one, so open file “CoursesController” and paste the code below:

[HttpPost]
public IActionResult AddCourse([FromBody] Course course)
{
                if (!ModelState.IsValid)
                {
                                Context.Response.StatusCode = 400;
                                return new ObjectResult(new CourseStatusModel { Id = 1 , Description= "Course model is invalid" });
                }
                else
                {
                   var addedCourse =  _registrationRepo.AddCourse(course);

                                if (addedCourse != null)
                                {
                                                string url = Url.RouteUrl("GetCourseById", new { courseId = course.Id }, Request.Scheme, Request.Host.ToUriComponent());

                                                Context.Response.StatusCode = 201;
                                                Context.Response.Headers["Location"] = url;
                                                return new ObjectResult(addedCourse);
                                }
                                else
                                {
                                                Context.Response.StatusCode = 400;
                                                return new ObjectResult(new CourseStatusModel { Id = 2, Description = "Failed to save course" });
                                }                
                }

}



About ASPHostPortal.com

We’re a company that works differently to most. Value is what we output and help our customers achieve, not how much money we put in the bank. It’s not because we are altruistic. It’s based on an even simpler principle. "Do good things, and good things will come to you".

Success for us is something that is continually experienced, not something that is reached. For us it is all about the experience – more than the journey. Life is a continual experience. We see the Internet as being an incredible amplifier to the experience of life for all of us. It can help humanity come together to explode in knowledge exploration and discussion. It is continual enlightenment of new ideas, experiences, and passions


Author Link


Corporate Address (Location)

ASPHostPortal
170 W 56th Street, Suite 121
New York, NY 10019
United States

Sign in