# 1.6.3. Building a API and testing

\--

* 1.Create **Api** folder in **controller** folder, right click  -> Add -> Controller -> Web API 2 Controller - Empty
* 2.Paste in Global.asax:

  ```
    public class MvcApplication : System.Web.HttpApplication
    {
        protected void Application_Start()
        {
            GlobalConfiguration.Configure(WebApiConfig.Register);
            AreaRegistration.RegisterAllAreas();
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
        }
    }
  ```
* 3.Write code in controller:

  ```
    private ApplicationDbContext _context;

        public CustomersController()
        {
            _context = new ApplicationDbContext();
        }

        // GET /api/customers
        public IEnumerable<Customer> GetCustomers()
        {
            return _context.Customers.ToList();
        }

        // GET /api/customers/1
        public Customer GetCustomers(int id)
        {
            var customer = _context.Customers.SingleOrDefault(c => c.Id == id);

            if (customer == null)
            {
                throw new HttpResponseException(HttpStatusCode.NotFound);
            }

            return customer;
        }

        // POST /api/customers
        [HttpPost]
        public Customer CreateCustomers(Customer customer)
        {
            if (!ModelState.IsValid)
            {
                throw new HttpResponseException(HttpStatusCode.BadRequest);
            }

            _context.Customers.Add(customer);
            _context.SaveChanges();

            return customer;
        }

        // PUT /api/customers/1
        [HttpPut]
        public void UpdateCustomers(int id, Customer customer)
        {
            if (!ModelState.IsValid)
            {
                throw new HttpResponseException(HttpStatusCode.BadRequest);
            }

            var customerInDb = _context.Customers.SingleOrDefault(c => c.Id == id);

            if (customerInDb == null)
            {
                throw new HttpResponseException(HttpStatusCode.NotFound);
            }

            customerInDb.Name = customer.Name;
            customerInDb.Birthday = customer.Birthday;
            customerInDb.IsSubscribeToNesletter = customer.IsSubscribeToNesletter;
            customerInDb.membershipTypeId = customer.membershipTypeId;

            _context.SaveChanges();
        }

        // PUT /api/customers/1
        [HttpDelete]
        public void DeleteCustomers(int id)
        {
            var customerInDb = _context.Customers.SingleOrDefault(c => c.Id == id);

            if (customerInDb == null)
            {
                throw new HttpResponseException(HttpStatusCode.NotFound);
            }

            _context.Customers.Remove(customerInDb);
            _context.SaveChanges();
        }
  ```
* 4.Test API
  * Open the browser and type: <http://localhost:3968/Api/Customers>
  * use POSTman
    * post
      * set header
        * key: content-type
        * value: application/json
      * set body

        ```
          {
              "Name": "Sea123",
              "IsSubscribeToNesletter": true,
              "membershipType": null,
              "membershipTypeId": 2,
              "Birthday": "2001/12/11"
          }
        ```


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