ASP.Net Simple Web API

Here, I would like to describe how to create a HTTP service using the Web API in ASP.NET and I will explain how to create a client consume the Web API.

In this tutorial I will explain how to do Create, Update, Retrieve and Delete (CRUD) operations in a HTTP service.

In this tutorial I will explain a very simple Web Application Programing Interface (API) to manage employee records. Each employee contains an Employee ID (UID), Name, Address and City.

This article explains the first three points.

Create HTTP service using ASP.NET Web API

Step 1: Start VS2012 then select "File" -> "New" -> "Project...".



Step 2: Web -> ASP.NET MVC 4 Web Application then click OK.

Step 3: Web API then click OK.



Step 4: Adding MODEL

A model is an object that represents the data in your application. In the ASP.NET Web API, you can use strongly typed CLR objects as models and they will automatically be serialized to XML or JSON for the client.

Here I have created a class named Employee.

In Solution Explorer, right-click the Models folder. From the context menu, select Add, then select Class. Name the class "Employee".



Adding the following properties to the Employee class.

Step 5: Adding Controller

In the ASP.NET Web API, a controller is a class that handles HTTP requests from the client. The New Project wizard created two controllers for you when it created the project. To see them, expand the Controllers folder in the Solution Explorer.

• HomeController is a traditional ASP.NET MVC controller. It is responsible for serving HTML pages for the site and is not directly related to our web API.
• ValuesController is an example WebAPI controller.

Proceed to and delete ValuesController by right-clicking the file in Solution Explorer and selecting Delete. Now add a new controller, as follows.

In Solution Explorer, right-click the the Controllers folder. Select Add and then select Controller.

In the Add Controller window, name the controller EmployeeController. In the template dropdown list, select Empty API controller. Then Click oK.

Add this namespace to the controller class

Note: All method names should begin with Get.

To get a list of all employees add this method to the EmployeeController class:

This method return list of all employee. URI for this method is: "/api/Employee?City=City"

To get an employee by ID add this method to the EmployeeController class.

This method returns an employee of a given uid. If the uid is not available in the list then it throws an exception with status code NotFound. The URI for this method is: /api/Employee?id=id”.