.Net MVC

What you will learn in Pro-Developer Program:

Here, in this article we will learn ASP.NET Web API 2 action method return types.

A Web API 2 action method return types can be any of the following :

• Void
• HttpResponseMessage
• IHttpActionResult
• Other type or Complex type

Void

When an ASP.NET Web API return type is void, it will return an empty HTTP response.

In the following example a web API with void return:

Example

public class SampleController : ApiController
{
  public void Post()
   {
            
   }
}

Note: We are using fiddler to call Web API, it is a free web debugging proxy which logs all HTTP(s) traffic between your computer and the Internet

Result

Calling sample web API in fiddler

 

It is returning status code 204 No Content (an empty HTTP response)

 

HttpResponseMessage

• When Web API return type is HttpResponseMessage, Web API converts the return value directly into an HTTP response message.
• We can set the status code, content as per our requirement.

In the following example a web API with HttpResponseMessage return:

Example

public HttpResponseMessage Get()
{
    HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.OK, "value1");            
    return response;
}

Result

Calling sample Web API with HTTP GET request

 

In Response, It is returning status code 200 OK and Content

 

Note:Web API serialized model into the response body based on request header formatter

In the following example a web API return HttpResponseMessage with list of Countries in response body:

Example

public HttpResponseMessage Get()
{
   // list of Countries
   List Countries = new List();
    Country country = new Country();
    country.ID = 1;
    country.CountryName = "USA";
    country.Capital = "Washington";
    Countries.Add(country);
        
    //Countries to the response body.             
    HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.OK, Countries);            
    return response;
}

Result

In Response, It is returning status code 200 OK and Content

 

IHttpActionResult

IHttpActionResult is introduced in Web API 2, IHttpActionResult interface acts like a factory for HttpResponseMessage.

There are some advantages of using the IHttpActionResult over HttpResponseMessage

• The code is cleaner and easier to read
• Unit testing for controller action methods become easy
• It comes with custom built in responses
  • Ok
  • NotFound
  • Exception
  • Unauthorized
  • BadRequest
  • Conflict
  • Redirect

In the following example a web API return IHttpActionResult with list of Countries in response body:

Example

public IHttpActionResult Get(int id)
{
   // list of Countries
   List Countries = new List();
    Country country = new Country();
    country.ID = 1;
    country.CountryName = "USA";
    country.Capital = "Washington";
    Countries.Add(country);
    
    //finding country based on provided id
    var result = Countries.FirstOrDefault(x=> x.ID ==id);
    if (result == null)
    {
        //create a 404 (Not Found) response
        return NotFound();                
    }
    else
    {
        //creates a 200 (OK) response that contains the country
        return Ok(result);
    }
}

Result

Calling sample web API with HTTP GET request and id

 

In Response, It is returning status code 200 OK and Content

 

Calling sample web API with HTTP GET request and id(which is not exist)

 

In Response, It is returning status code 404 Not Found

 

Other type or Complex type

• A Web API can return other or custom complex type
• Web API serialize value and return it into the response body
• The response status code 200 OK
• But in this approach we cannot directly return an error code, still we can throw an HttpResponseException for error codes

In the following example a web API with Complex return type:

Example

public class CountryController : ApiController
{
    public IEnumerable Get()
    {
        List Countries = new List();
        Country country = new Country();
        country.ID = 1;
        country.CountryName = "USA";
        country.Capital = "Washington";
        Countries.Add(country);
        return Countries;
    }
}

Result

Calling Country web API with HTTP GET request

 

In Response, It is returning status code 200 OK and Content

 

Today we learn how to use antiforgery token validation Key in ajax reqeust (MVC)

first we create a Action with attributes antiforgery key.. 

Now we add @Html.AntiForgeryToken() in view and then  create ajax call for above action

Below is the ajax request.

After ajax request now we can verify request  with AntiForgeryToken .

I hope this lession will help you increase your Knowledge. if you like this lession the vote me.

Let us know if you have any query and concern.

Any web application has two main execution steps first understanding the request and depending on the type of the request sending out appropriate response. MVC life cycle also follow same principle. 

MVC life cycle divided into two section. 1) Creating the request object 2) Creating response object

Creating the request object: -The request object creation has four major steps.

Step 1 Fill route: - MVC requests are mapped to route tables which in turn specify which controller and action to be invoked. So if the request is the first request the first thing is to fill the route table with routes collection. This filling of route table happens in the global.asax file.

Step 2 Fetch route: - Depending on the URL sent “UrlRoutingModule” searches the route table to create “RouteData” object which has the details of which controller and action to invoke.

Step 3 Request context created: - The “RouteData” object is used to create the “RequestContext” object.

Step 4 Controller instance created: - This request object is sent to “MvcHandler” instance to create the controller class instance. Once the controller class object is created it calls the “Execute” method of the controller class.

Creating Response object: - This phase has two steps executing the action and finally sending the response as a result to the view.

Tradional asp.net had slower server side response feedback to the server with the MVC concept on webapi there were faster responses from the server side for client requests.

Optimization of code was main purpose and object oriented analysis gained further more predominance.

Easy documentation and accessibilities. And customizations.

A service-level agreement (SLA) is a contract between a service provider and its internal or external customers that documents what services the provider will furnish.

SLAs originated with network service providers, but are now widely used by telecommunicationservice providers and cloud computing service providers. Corporate IT organizations, particularly those that have embraced IT service management (ITSM), enter SLAs with their in-house customers (users in other departments within the enterprise). An IT department creates an SLA so that its services can be measured, justified and perhaps compared with those of outsourcing vendors.

SLAs measure the service provider’s performance and quality in a number of ways. Some metrics that SLAs may specify include:

Availability and uptime -- the percentage of the time services will be available

The number of concurrent users that can be served

Specific performance benchmarks to which actual performance will be periodically compared

Application response time

The schedule for notification in advance of network changes that may affect users

Help desk response time for various classes of problems

Usage statistics that will be provided.

In addition to establishing performance metrics, an SLA may include a plan for addressing downtime and documentation for how the service provider will compensate customers in the event of a contract breach. SLAs, once established, should be periodically reviewed and updated to reflect changes in technology and the impact of any new regulatory directives (changes to the PCI DSS standard, for instance).