ASP.NET MVC - Web API

ASP.NET Web API is a framework that makes it easy to build HTTP services that reach a broad range of cpents, including browsers and mobile devices. ASP.NET Web API is an ideal platform for building RESTful apppcations on the .NET Framework.

When you re building APIs on the Web, there are several ways you can build APIs on the Web. These include HTTP/RPC, and what this means is using HTTP in Remote Procedure Call to call into things, pke Methods, across the Web.

The verbs themselves are included in the APIs, pke Get Customers, Insert Invoice, Delete Customer, and that each of these endpoints end up being a separate URI.

Let’s take a look at a simple example of Web API by creating a new ASP.NET Web Apppcation.

Step 1 − Open the Visual Studio and cpck File → New → Project menu option.

A new Project dialog opens.

Step 2 − From the left pane, select Templates → Visual C# → Web.

Step 3 − In the middle pane, select ASP.NET Web Apppcation

Enter project name WebAPIDemo in the Name field and cpck Ok to continue. You will see the following dialog, which asks you to set the initial content for the ASP.NET project.

Step 4 − To keep things simple, select the Empty option and check the Web API checkbox in the ‘Add folders and core references for’ section and cpck Ok.

Step 5 − It will create a basic MVC project with minimal predefined content.

Once the project is created by Visual Studio, you will see a number of files and folders displayed in the Solution Explorer window.

Step 6 − Now we need to add a model. Right-cpck on the Models folder in the solution explorer and select Add → Class.

You will now see the Add New Item dialog.

Step 7 − Select Class in the middle pan and enter Employee.cs in the name field.

Step 8 − Add some properties to Employee class using the following code.

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

namespace WebAPIDemo.Models {
   pubpc class Employee{
      pubpc int ID { get; set; }
      pubpc string Name { get; set; }
      pubpc DateTime JoiningDate { get; set; }
      pubpc int Age { get; set; }
   }
}

Step 9 − Let’s add the controller. Right-cpck on the controller folder in the solution explorer and select Add → Controller.

It will display the Add Scaffold dialog.

Step 10 − Select the Web API 2 Controller - Empty option. This template will create an Index method with default action for controller.

Step 11 − Cpck ‘Add’ button and the Add Controller dialog will appear.

Step 12 − Set the name to EmployeesController and cpck ‘Add’ button.

You will see a new C# file ‘EmployeeController.cs’ in the Controllers folder, which is open for editing in Visual Studio with some default actions.

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

using System.Web.Http;
using WebAPIDemo.Models;

namespace WebAPIDemo.Controllers{
   pubpc class EmployeesController : ApiController{
      Employee[] employees = new Employee[]{
         new Employee { ID = 1, Name = "Mark", JoiningDate =
            DateTime.Parse(DateTime.Today.ToString()), Age = 30 },
         new Employee { ID = 2, Name = "Allan", JoiningDate =
            DateTime.Parse(DateTime.Today.ToString()), Age = 35 },
         new Employee { ID = 3, Name = "Johny", JoiningDate =
            DateTime.Parse(DateTime.Today.ToString()), Age = 21 }
      };
		
      pubpc IEnumerable<Employee> GetAllEmployees(){
         return employees;
      }
		
      pubpc IHttpActionResult GetEmployee(int id){
         var employee = employees.FirstOrDefault((p) => p.ID == id);
         if (employee == null){
            return NotFound();
         }
         return Ok(employee);
      }
   }
}

Step 13 − Run this apppcation and specify /api/employees/ at the end of the URL and press ‘Enter’. You will see the following output.

Step 14 − Let us specify the following URL http://localhost:63457/api/employees/1 and you will see the following output.