Ambily K K - ASP.NET Web API 2: Beginner Guide

Our first step will be to create an ASP.NET MVC project based on the Web API template, as shown in Figure 1. Figure 1: Creating an ASP.NET MVC project based on the Web API template Next, well create a sample model inside the model folder in the MVC solution. Right click on the Model folder from the solution explorer and select Add -> Class as shown in Figure 2. Figure 2: Add new Model For this walk-through, I am using the Product model defined in Listing 1. Listing 1: Defining the Product model public class Product { public int Id { get ; set ; } public string Name { get ; set ; } public string Category { get ; set ; } public decimal Price { get ; set ; } } Once the product model is ready, let us create a new API controller inside the controllers folder to process the Product model. By default, an MVC project based on the Web API template adds two controllers: one inherited from the Controller class and the other from ApiController class.

Right-click the controllers folder in Solution Explorer and add a new controller by selecting the Empty API controller option under template as shown in Figure 3. Figure 3: Add Empty API Controller Provide appropriate name for the new controller; say ProductsController. Figure 4: Add Controller ProductsController will define two methods for getting list of products and selected product based on product id. The code for the sample controller should look like that shown in Listing 2. Listing 2: Adding an ApiController class to the sample project public class ProductsController : ApiController { //Define the products list List < Product > products = new List < Product >(); ///
/// Web API method to return list of products /// /// public IEnumerable < Product > GetAllProducts() { GetProducts(); return products; } private void GetProducts() { products.Add( new Product { Id = 1, Name = "Television" , Category = "Electronic" , Price = 82000 }); products.Add( new Product { Id = 2, Name = "Refrigerator" , Category = "Electronic" , Price = 23000 }); products.Add( new Product { Id = 3, Name = "Mobiles" , Category = "Electronic" , Price = 20000 }); products.Add( new Product { Id = 4, Name = "Laptops" , Category = "Electronic" , Price = 45000 }); products.Add( new Product { Id = 5, Name = "iPads" , Category = "Electronic" , Price = 67000 }); products.Add( new Product { Id = 6, Name = "Toys" , Category = "Gift Items" , Price = 15000 }); } ///
/// Web API method to retrurn selected product based on the passed id /// /// /// public IEnumerable < Product > GetProducts( int selectedId) { if (products.Count() > 0) { return products.Where(p => p.Id == selectedId); } else { GetProducts(); return products.Where(p => p.Id == selectedId); } } } Run the project and access the API by appending the uniform resource locator (URL) with /api/Products , as in http://localhost: 59509/api/Products . This api call will return the list of Products.

We can also access the GetProducts method by passing the SelectedId argument as part of the query string: http://localhost:59509/api/Products?SelectedId=2 . By default Web API returns JSON data, so when you run the Web API directly from browser, it will prompt to save or open the JSON output. Following Figure shows the api output for the /api/Products request. Figure 5: Web API Response - JSON format