Reading these MVC interview questions does not mean you will go and clear MVC interviews. The purpose of this article is to quickly brush up your MVC knowledge before you go for MVC interviews. This article does not teach MVC, it’s a last minute revision sheet before going for MVC interviews.

If you want to learn MVC from scratch, start by reading Learn MVC ( Model view controller) step by step 7 days or you can also start with my step by step MVC (Model View Controller) video series from YouTube.

If you want to learn MVC 5 in a short time i.e. 2 days a.k.a 16 hours below is a video series for the same.

http://www.codeproject.com/KB/aspnet/556995/mockup__1_.png

Need help to improve this article

I have tried my level best to cover what questions i have faced in MVC interviews. But i feel the below questions are not enough and in real MVC interview's much more is asked. If you can share your question in the comment below. I would love to incorporate them in this article so that others are benefited.
If your question is great and i like it i will ship you a free copy of my .NET interview question book only in India ( sorry i am not so rich for outside countries).

What is MVC (Model View Controller)?

MVC is an architectural pattern which separates the representation and user interaction. It’s divided into three broader sections, Model, View, and Controller. Below is how each one of them handles the task.

· The View is responsible for the look and feel.

· Model represents the real world object and provides data to the View.

· The Controller is responsible for taking the end user request and loading the appropriate Model and View.

http://www.codeproject.com/KB/aspnet/556995/1.jpg

Figure: MVC (Model view controller)

Explain MVC application life cycle?

There are six broader events which occur in MVC application life cycle below diagrams summarize it.

http://www.codeproject.com/KB/aspnet/556995/MVCLifeCycle.jpg

Image Courtesy: - http://www.dotnetinterviewquestions.in/article_explain-mvc-application-life-cycle_210.html

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 application life cycle is not different it has two main phases first creating the request object and second sending our response to the browser.

Creating the request object: -The request object creation has four major steps. Below is the detail explanation of the same.

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.

Is MVC suitable for both Windows and Web applications?

The MVC architecture is suited for a web application than Windows. For Window applications, MVP, i.e., “Model View Presenter” is more applicable. If you are using WPF and Silverlight, MVVM is more suitable due to bindings.

What are the benefits of using MVC?

There are two big benefits of MVC:

· Separation of concerns is achieved as we are moving the code-behind to a separate class file. By moving the binding code to a separate class file we can reuse the code to a great extent.

· Automated UI testing is possible because now the behind code (UI interaction code) has moved to a simple .NET class. This gives us opportunity to write unit tests and automate manual testing.

Is MVC different from a three layered architecture?

MVC is an evolution of a three layered traditional architecture. Many components of the three layered architecture are part of MVC. So below is how the mapping goes:

Functionality	Three layered / tiered architecture	Model view controller architecture
Look and Feel	User interface	View
UI logic	User interface	Controller
Business logic /validations	Middle layer	Model
Request is first sent to	User interface	Controller
Accessing data	Data access layer	Data Access Layer

http://www.codeproject.com/KB/aspnet/556995/2.jpg

Figure: Three layered architecture

What is the latest version of MVC?

MVC 6 is the latest version which is also termed as ASP VNEXT.

What is the difference between each version of MVC 2, 3 , 4, 5 and 6?

MVC 6

ASP.NET MVC and Web API has been merged in to one.

Dependency injection is inbuilt and part of MVC.

Side by side - deploy the runtime and framework with your application

Everything packaged with NuGet, Including the .NET runtime itself.

New JSON based project structure.

No need to recompile for every change. Just hit save and refresh the browser.

Compilation done with the new Roslyn real-time compiler.

vNext is Open Source via the .NET Foundation and is taking public contributions.

vNext (and Rosyln) also runs on Mono, on both Mac and Linux today.

MVC 5

One ASP.NET

Attribute based routing

Asp.Net Identity

Bootstrap in the MVC template

Authentication Filters

Filter overrides

MVC 4

ASP.NET Web API

Refreshed and modernized default project templates

New mobile project template

Many new features to support mobile apps

Enhanced support for asynchronous methods

MVC 3

Razor

Readymade project templates

HTML 5 enabled templates

Support for Multiple View Engines

JavaScript and Ajax

Model Validation Improvements

MVC 2

Client-Side Validation

Templated Helpers

Areas

Asynchronous Controllers

Html.ValidationSummary Helper Method

DefaultValueAttribute in Action-Method Parameters

Binding Binary Data with Model Binders

DataAnnotations Attributes

Model-Validator Providers

New RequireHttpsAttribute Action Filter

Templated Helpers

Display Model-Level Errors

What are HTML helpers in MVC?

HTML helpers help you to render HTML controls in the view. For instance if you want to display a HTML textbox on the view , below is the HTML helper code.

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<%= Html.TextBox("LastName") %>

For checkbox below is the HTML helper code. In this way we have HTML helper methods for every HTML control that exists.

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<%= Html.CheckBox("Married") %>

What is the difference between “HTML.TextBox” vs “HTML.TextBoxFor”?

Both of them provide the same HTML output, “HTML.TextBoxFor” is strongly typed while “HTML.TextBox” isn’t. Below is a simple HTML code which just creates a simple textbox with “CustomerCode” as name.

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Html.TextBox("CustomerCode")

Below is “Html.TextBoxFor” code which creates HTML textbox using the property name ‘CustomerCode” from object “m”.

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Html.TextBoxFor(m => m.CustomerCode)

In the same way we have for other HTML controls like for checkbox we have “Html.CheckBox” and “Html.CheckBoxFor”.

What is routing in MVC?

Routing helps you to define a URL structure and map the URL with the controller.

For instance let’s say we want that when a user types “http://localhost/View/ViewCustomer/”, it goes to the “Customer” Controller and invokes the DisplayCustomer action. This is defined by adding an entry in to theroutes collection using the maproute function. Below is the underlined code which shows how the URL structure and mapping with controller and action is defined.

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routes.MapRoute(

"View", // Route name

"View/ViewCustomer/{id}", // URL with parameters

new { controller = "Customer", action = "DisplayCustomer",

id = UrlParameter.Optional }); // Parameter defaults

Where is the route mapping code written?

The route mapping code is written in "RouteConfig.cs" file and registered using "global.asax" application start event.

Can we map multiple URL’s to the same action?

Yes, you can, you just need to make two entries with different key names and specify the same controller and action.

Explain attribute based routing in MVC?

This is a feature introduced in MVC 5. By using the "Route" attribute we can define the URL structure. For example in the below code we have decorated the "GotoAbout" action with the route attribute. The route attribute says that the "GotoAbout" can be invoked using the URL structure "Users/about".

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public class HomeController : Controller

{

[Route("Users/about")]

public ActionResult GotoAbout()

{

return View();

}

What is the advantage of defining route structures in the code?

Most of the time developers code in the action methods. Developers can see the URL structure right upfront rather than going to the “routeconfig.cs” and see the lengthy codes. For instance in the below code the developer can see right upfront that the “GotoAbout” action can be invoked by four different URL structure.

This is much user friendly as compared to scrolling through the “routeconfig.cs” file and going through the length line of code to figure out which URL structure is mapped to which action.

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public class HomeController : Controller

{

[Route("Users/about")]

[Route("Users/WhoareWe")]

[Route("Users/OurTeam")]

[Route("Users/aboutCompany")]

public ActionResult GotoAbout()

{

return View();

}

How can we navigate from one view to another using a hyperlink?

By using the ActionLink method as shown in the below code. The below code will create a simple URL which helps to navigate to the “Home” controller and invoke the GotoHome action.

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<%= Html.ActionLink("Home","Gotohome") %>

How can we restrict MVC actions to be invoked only by GET or POST?

We can decorate the MVC action with the HttpGet or HttpPost attribute to restrict the type of HTTP calls. For instance you can see in the below code snippet the DisplayCustomer action can only be invoked by HttpGet. If we try to make HTTP POST on DisplayCustomer, it will throw an error.

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[HttpGet]

public ViewResult DisplayCustomer(int id)

{

Customer objCustomer = Customers[id];

return View("DisplayCustomer",objCustomer);

}

How can we maintain sessions in MVC?

Sessions can be maintained in MVC by three ways: tempdata, viewdata, and viewbag.

What is the difference between tempdata, viewdata, and viewbag?

http://www.codeproject.com/KB/aspnet/556995/3.jpg

Figure: Difference between tempdata, viewdata, and viewbag

· Temp data - Helps to maintain data when you move from one controller to another controller or from one action to another action. In other words when you redirect, tempdata helps to maintain data between those redirects. It internally uses session variables.

· View data - Helps to maintain data when you move from controller to view.

· View Bag - It’s a dynamic wrapper around view data. When you use Viewbag type, casting is not required. It uses the dynamic keyword internally.

http://www.codeproject.com/KB/aspnet/556995/4.jpg

Figure: dynamic keyword

· Session variables - By using session variables we can maintain data from any entity to any entity.

· Hidden fields and HTML controls - Helps to maintain data from UI to controller only. So you can send data from HTML controls or hidden fields to the controller using POST or GET HTTP methods.

Below is a summary table which shows the different mechanisms for persistence.

Maintains data between	ViewData/ViewBag	TempData	Hidden fields	Session
Controller to Controller	No	Yes	No	Yes
Controller to View	Yes	No	No	Yes
View to Controller	No	No	Yes	Yes

What is difference between TempData and ViewData ?

“TempData” maintains data for the complete request while “ViewData” maintains data only from Controller to the view.

Does “TempData” preserve data in the next request also?

“TempData” is available through out for the current request and in the subsequent request it’s available depending on whether “TempData” is read or not.

So if “TempData” is once read it will not be available in the subsequent request.

What is the use of Keep and Peek in “TempData”?

Once “TempData” is read in the current request it’s not available in the subsequent request. If we want “TempData” to be read and also available in the subsequent request then after reading we need to call “Keep” method as shown in the code below.

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@TempData[“MyData”];

TempData.Keep(“MyData”);

The more shortcut way of achieving the same is by using “Peek”. This function helps to read as well advices MVC to maintain “TempData” for the subsequent request.

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string str = TempData.Peek("Td").ToString();

If you want to read more in detail you can read from this detailed blog on MVC Peek and Keep.

What are partial views in MVC?

Partial view is a reusable view (like a user control) which can be embedded inside other view. For example let’s say all your pages of your site have a standard structure with left menu, header, and footer as shown in the image below.

http://www.codeproject.com/KB/aspnet/556995/5.jpg

Figure: Partial views in MVC

For every page you would like to reuse the left menu, header, and footer controls. So you can go and create partial views for each of these items and then you call that partial view in the main view.

How did you create a partial view and consume it?

When you add a view to your project you need to check the “Create partial view” check box.

http://www.codeproject.com/KB/aspnet/556995/6.jpg

Figure: Create partial view

Once the partial view is created you can then call the partial view in the main view using theHtml.RenderPartial method as shown in the below code snippet:

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<body>

<div>

<% Html.RenderPartial("MyView"); %>

</div>

</body>

How can we do validations in MVC?

One of the easiest ways of doing validation in MVC is by using data annotations. Data annotations are nothing but attributes which can be applied on model properties. For example, in the below code snippet we have a simple Customer class with a property customercode.

This CustomerCode property is tagged with a Required data annotation attribute. In other words if this model is not provided customer code, it will not accept it.

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public class Customer

{

[Required(ErrorMessage="Customer code is required")]

public string CustomerCode

{

set;

get;

}

In order to display the validation error message we need to use the ValidateMessageFor method which belongs to the Html helper class.

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<% using (Html.BeginForm("PostCustomer", "Home", FormMethod.Post))

{ %>

<%=Html.TextBoxFor(m => m.CustomerCode)%>

<%=Html.ValidationMessageFor(m => m.CustomerCode)%>

<%}%>

Later in the controller we can check if the model is proper or not by using the ModelState.IsValid property and accordingly we can take actions.

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public ActionResult PostCustomer(Customer obj)

{

if (ModelState.IsValid)

{

obj.Save();

return View("Thanks");

}

else

{

return View("Customer");

}

Below is a simple view of how the error message is displayed on the view.

http://www.codeproject.com/KB/aspnet/556995/7.jpg

Figure: Validations in MVC

Can we display all errors in one go?

Yes, we can; use the ValidationSummary method from the Html helper class.

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<%= Html.ValidationSummary() %>

What are the other data annotation attributes for validation in MVC?

If you want to check string length, you can use StringLength.

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[StringLength(160)]

public string FirstName { get; set; }

In case you want to use a regular expression, you can use the RegularExpression attribute.

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[RegularExpression(@"[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,4}")]public string Email { get; set; }

If you want to check whether the numbers are in range, you can use the Range attribute.

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[Range(10,25)]public int Age { get; set; }

Sometimes you would like to compare the value of one field with another field, we can use the Compareattribute.

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public string Password { get; set; }[Compare("Password")]public string ConfirmPass { get; set; }

In case you want to get a particular error message , you can use the Errors collection.

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var ErrMessage = ModelState["Email"].Errors[0].ErrorMessage;

If you have created the model object yourself you can explicitly call TryUpdateModel in your controller to check if the object is valid or not.

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TryUpdateModel(NewCustomer);

In case you want add errors in the controller you can use the AddModelError function.

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ModelState.AddModelError("FirstName", "This is my server-side error.");

How can we enable data annotation validation on client side?

It’s a two-step process: first reference the necessary jQuery files.

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The second step is to call the EnableClientValidation method.

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<% Html.EnableClientValidation(); %>

What is Razor in MVC?

It’s a light weight view engine. Till MVC we had only one view type, i.e., ASPX. Razor was introduced in MVC 3.

Why Razor when we already have ASPX?

Razor is clean, lightweight, and syntaxes are easy as compared to ASPX. For example, in ASPX to display simple time, we need to write:

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<%=DateTime.Now%>

In Razor, it’s just one line of code:

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@DateTime.Now

So which is a better fit, Razor or ASPX?

As per Microsoft, Razor is more preferred because it’s light weight and has simple syntaxes.

How can you do authentication and authorization in MVC?

You can use Windows or Forms authentication for MVC.

How to implement Windows authentication for MVC?

For Windows authentication you need to modify the web.config file and set the authentication mode to Windows.

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</authorization>

Then in the controller or on the action, you can use the Authorize attribute which specifies which users have access to these controllers and actions. Below is the code snippet for that. Now only the users specified in the controller and action can access it.

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[Authorize(Users= @"WIN-3LI600MWLQN\Administrator")]

public class StartController : Controller

{

// GET: /Start/

[Authorize(Users = @"WIN-3LI600MWLQN\Administrator")]

public ActionResult Index()

{

return View("MyView");

}

How do you implement Forms authentication in MVC?

Forms authentication is implemented the same way as in ASP.NET. The first step is to set the authentication mode equal to Forms. The loginUrl points to a controller here rather than a page.

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</authentication>

We also need to create a controller where we will check if the user is proper or not. If the user is proper we will set the cookie value.

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public ActionResult Login()

{

if ((Request.Form["txtUserName"] == "Shiv") &&

(Request.Form["txtPassword"] == "Shiv@123"))

{

FormsAuthentication.SetAuthCookie("Shiv",true);

return View("About");

}

else

{

return View("Index");

}

All the other actions need to be attributed with the Authorize attribute so that any unauthorized user making a call to these controllers will be redirected to the controller (in this case the controller is “Login”) which will do the authentication.

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[Authorize]

PublicActionResult Default()

{

return View();

}

[Authorize]

publicActionResult About()

{

return View();

}

How to implement AJAX in MVC?

You can implement AJAX in two ways in MVC:

· AJAX libraries

· jQuery

Below is a simple sample of how to implement AJAX by using the “AJAX” helper library. In the below code you can see we have a simple form which is created by using the Ajax.BeginForm syntax. This form calls a controller action called getCustomer. So now the submit action click will be an asynchronous AJAX call.

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function OnSuccess(data1)

{

// Do something here

}

</script>

<div>

var AjaxOpt = new AjaxOptions{OnSuccess="OnSuccess"};

<% using (Ajax.BeginForm("getCustomer","MyAjax",AjaxOpt)) { %>

<%} %>

In case you want to make AJAX calls on hyperlink clicks, you can use the Ajax.ActionLink function as shown in the below code.

http://www.codeproject.com/KB/aspnet/556995/8.jpg

Figure: Implement AJAX in MVC

So if you want to create an AJAX asynchronous hyperlink by name GetDate which calls the GetDate function in the controller, below is the code for that. Once the controller responds, this data is displayed in the HTML DIVtag named DateDiv.

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<%:

Ajax.ActionLink("Get Date","GetDate",

new AjaxOptions {UpdateTargetId = "DateDiv" })

Below is the controller code. You can see how the GetDate function has a pause of 10 seconds.

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public class Default1Controller : Controller

{

public string GetDate()

{

Thread.Sleep(10000);

return DateTime.Now.ToString();

}

The second way of making an AJAX call in MVC is by using jQuery. In the below code you can see we are making an AJAX POST call to a URL /MyAjax/getCustomer. This is done by using $.post. All this logic is put into a function called GetData and you can make a call to the GetData function on a button or a hyperlink click event as you want.

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function GetData()

{

var url = "/MyAjax/getCustomer";

$.post(url, function (data)

{

$("#txtCustomerCode").val(data.CustomerCode);

$("#txtCustomerName").val(data.CustomerName);

}

)

}

What kind of events can be tracked in AJAX?

http://www.codeproject.com/KB/aspnet/556995/9.jpg

Figure: Tracked in AJAX

What is the difference between ActionResult and ViewResult?

· ActionResult is an abstract class while ViewResult derives from the ActionResult class.ActionResult has several derived classes like ViewResult, JsonResult, FileStreamResult, and so on.

· ActionResult can be used to exploit polymorphism and dynamism. So if you are returning different types of views dynamically, ActionResult is the best thing. For example in the below code snippet, you can see we have a simple action called DynamicView. Depending on the flag (IsHtmlView) it will either return a ViewResult or JsonResult.

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public ActionResult DynamicView()

{

if (IsHtmlView)

return View(); // returns simple ViewResult

else

return Json(); // returns JsonResult view

}

What are the different types of results in MVC?

Note: It’s difficult to remember all the 12 types. But some important ones you can remember for the interview are ActionResult, ViewResult, and JsonResult. Below is a detailed list for your interest:

There 12 kinds of results in MVC, at the top is the ActionResult class which is a base class that can have 11 subtypes as listed below:

1. ViewResult - Renders a specified view to the response stream

2. PartialViewResult - Renders a specified partial view to the response stream

3. EmptyResult - An empty response is returned

4. RedirectResult - Performs an HTTP redirection to a specified URL

5. RedirectToRouteResult - Performs an HTTP redirection to a URL that is determined by the routing engine, based on given route data

6. JsonResult - Serializes a given ViewData object to JSON format

7. JavaScriptResult - Returns a piece of JavaScript code that can be executed on the client

8. ContentResult - Writes content to the response stream without requiring a view

9. FileContentResult - Returns a file to the client

10. FileStreamResult - Returns a file to the client, which is provided by a Stream

11. FilePathResult - Returns a file to the client

What are ActionFilters in MVC?

ActionFilters help you to perform logic while an MVC action is executing or after an MVC action has executed.

http://www.codeproject.com/KB/aspnet/556995/10.jpg

Figure: ActionFilters in MVC

Action filters are useful in the following scenarios:

1. Implement post-processing logic before the action happens.

2. Cancel a current execution.

3. Inspect the returned value.

4. Provide extra data to the action.

You can create action filters by two ways:

· Inline action filter.

· Creating an ActionFilter attribute.

To create an inline action attribute we need to implement the IActionFilter interface. The IActionFilterinterface has two methods: OnActionExecuted and OnActionExecuting. We can implement pre-processing logic or cancellation logic in these methods.

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public class Default1Controller : Controller , IActionFilter

{

public ActionResult Index(Customer obj)

{

return View(obj);

}

void IActionFilter.OnActionExecuted(ActionExecutedContext filterContext)

{

Trace.WriteLine("Action Executed");

}

void IActionFilter.OnActionExecuting(ActionExecutingContext filterContext)

{

Trace.WriteLine("Action is executing");

}

The problem with the inline action attribute is that it cannot be reused across controllers. So we can convert the inline action filter to an action filter attribute. To create an action filter attribute we need to inherit fromActionFilterAttribute and implement the IActionFilter interface as shown in the below code.

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public class MyActionAttribute : ActionFilterAttribute , IActionFilter

{

void IActionFilter.OnActionExecuted(ActionExecutedContext filterContext)

{

Trace.WriteLine("Action Executed");

}

void IActionFilter.OnActionExecuting(ActionExecutingContext filterContext)

{

Trace.WriteLine("Action executing");

}

Later we can decorate the controllers on which we want the action attribute to execute. You can see in the below code I have decorated the Default1Controller with the MyActionAttribute class which was created in the previous code.

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[MyActionAttribute]

public class Default1Controller : Controller

{

public ActionResult Index(Customer obj)

{

return View(obj);

}

Can we create our custom view engine using MVC?

Yes, we can create our own custom view engine in MVC. To create our own custom view engine we need to follow three steps:

Let’ say we want to create a custom view engine where in the user can type a command like “<DateTime>” and it should display the current date and time.

Step 1: We need to create a class which implements the IView interface. In this class we should write the logic of how the view will be rendered in the render function. Below is a simple code snippet for that.

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public class MyCustomView : IView

{

private string _FolderPath; // Define where our views are stored

public string FolderPath

{

get { return _FolderPath; }

set { _FolderPath = value; }

}

public void Render(ViewContext viewContext, System.IO.TextWriter writer)

{

// Parsing logic <dateTime>

// read the view file

string strFileData = File.ReadAllText(_FolderPath);

// we need to and replace <datetime> datetime.now value

string strFinal = strFileData.Replace("<DateTime>", DateTime.Now.ToString());

// this replaced data has to sent for display

writer.Write(strFinal);

}

Step 2: We need to create a class which inherits from VirtualPathProviderViewEngine and in this class we need to provide the folder path and the extension of the view name. For instance, for Razor the extension is “cshtml”; for aspx, the view extension is “.aspx”, so in the same way for our custom view, we need to provide an extension. Below is how the code looks like. You can see the ViewLocationFormats is set to the Views folder and the extension is “.myview”.

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public class MyViewEngineProvider : VirtualPathProviderViewEngine

{

// We will create the object of Mycustome view

public MyViewEngineProvider() // constructor

{

// Define the location of the View file

this.ViewLocationFormats = new string[] { "~/Views/{1}/{0}.myview",

"~/Views/Shared/{0}.myview" }; //location and extension of our views

}

protected override IView CreateView(

ControllerContext controllerContext, string viewPath, string masterPath)

{

var physicalpath = controllerContext.HttpContext.Server.MapPath(viewPath);

MyCustomView obj = new MyCustomView(); // Custom view engine class

obj.FolderPath = physicalpath; // set the path where the views will be stored

return obj; // returned this view paresing

// logic so that it can be registered in the view engine collection

}

protected override IView CreatePartialView(ControllerContext controllerContext, string partialPath)

{

var physicalpath = controllerContext.HttpContext.Server.MapPath(partialPath);

MyCustomView obj = new MyCustomView(); // Custom view engine class

obj.FolderPath = physicalpath; // set the path where the views will be stored

return obj;

// returned this view paresing logic

// so that it can be registered in the view engine collection

}

Step 3: We need to register the view in the custom view collection. The best place to register the custom view engine in the ViewEngines collection is the global.asax file. Below is the code snippet for that.

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protected void Application_Start()

{

// Step3 :- register this object in the view engine collection

ViewEngines.Engines.Add(new MyViewEngineProvider());

…..

}

Below is a simple output of the custom view written using the commands defined at the top.

http://www.codeproject.com/KB/aspnet/556995/11.jpg

Figure: Custom view engine using MVC

If you invoke this view, you should see the following output:

http://www.codeproject.com/KB/aspnet/556995/12.jpg

How to send result back in JSON format in MVC

In MVC, we have the JsonResult class by which we can return back data in JSON format. Below is a simple sample code which returns back a Customer object in JSON format using JsonResult.

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public JsonResult getCustomer()

{

Customer obj = new Customer();

obj.CustomerCode = "1001";

obj.CustomerName = "Shiv";

return Json(obj,JsonRequestBehavior.AllowGet);

}

Below is the JSON output of the above code if you invoke the action via the browser.

http://www.codeproject.com/KB/aspnet/556995/13.jpg

What is WebAPI?

HTTP is the most used protocol. For the past many years, browser was the most preferred client by which we consumed data exposed over HTTP. But as years passed by, client variety started spreading out. We had demand to consume data on HTTP from clients like mobile, JavaScript, Windows applications, etc.

For satisfying the broad range of clients REST was the proposed approach. You can read more about REST from the WCF chapter.

WebAPI is the technology by which you can expose data over HTTP following REST principles.

But WCF SOAP also does the same thing, so how does WebAPI differ?

	SOAP	WEB API
Size	Heavy weight because of complicated WSDL structure.	Light weight, only the necessary information is transferred.
Protocol	Independent of protocols.	Only for HTTP protocol
Formats	To parse SOAP message, the client needs to understand WSDL format. Writing custom code for parsing WSDL is a heavy duty task. If your client is smart enough to create proxy objects like how we have in .NET (add reference) then SOAP is easier to consume and call.	Output of WebAPI are simple string messages, JSON, simple XML format, etc. So writing parsing logic for that is very easy.
Principles	SOAP follows WS-* specification.	WebAPI follows REST principles. (Please refer to REST in WCF chapter.)

With WCF you can implement REST, so why WebAPI?

WCF was brought into implement SOA, the intention was never to implement REST. WebAPI is built from scratch and the only goal is to create HTTP services using REST. Due to the one point focus for creating REST service, WebAPI is more preferred.

How to implement WebAPI in MVC

Below are the steps to implement WebAPI:

Step 1: Create the project using the WebAPI template.

http://www.codeproject.com/KB/aspnet/556995/14.jpg

Figure: Implement WebAPI in MVC

Step 2: Once you have created the project you will notice that the controller now inherits from ApiControllerand you can now implement POST, GET, PUT, and DELETE methods of the HTTP protocol.

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public class ValuesController : ApiController

{

// GET api/values

public IEnumerable<string> Get()

{

return new string[] { "value1", "value2" };

}

// GET api/values/5

public string Get(int id)

{

return "value";

}

// POST api/values

public void Post([FromBody]string value)

{

}

// PUT api/values/5

public void Put(int id, [FromBody]string value)

{

}

// DELETE api/values/5

public void Delete(int id)

{

}

Step 3: If you make an HTTP GET call you should get the below results:

http://www.codeproject.com/KB/aspnet/556995/15.jpg

Figure: HTTP

How can we detect that an MVC controller is called by POST or GET?

To detect if the call on the controller is a POST action or a GET action we can use the Request.HttpMethodproperty as shown in the below code snippet.

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public ActionResult SomeAction()

{

if (Request.HttpMethod == "POST")

{

return View("SomePage");

}

else

{

return View("SomeOtherPage");

}

What is bundling and minification in MVC?

Bundling and minification helps us improve request load times of a page thus increasing performance.

How does bundling increase performance?

Web projects always need CSS and script files. Bundling helps us combine multiple JavaScript and CSS files in to a single entity thus minimizing multiple requests in to a single request.

For example consider the below web request to a page . This page consumes two JavaScript files Javascript1.jsand Javascript2.js. So when this is page is requested it makes three request calls:

· One for the Index page.

· Two requests for the other two JavaScript files: Javascript1.js and Javascript2.js.

The below scenario can become worse if we have a lot of JavaScript files resulting in multiple requests, thus decreasing performance. If we can somehow combine all the JS files into a single bundle and request them as a single unit that would result in increased performance (see the next figure which has a single request).

http://www.codeproject.com/KB/aspnet/556995/image1.png

http://www.codeproject.com/KB/aspnet/556995/image2.png

So how do we implement bundling in MVC?

Open BundleConfig.cs from the App_Start folder.

http://www.codeproject.com/KB/aspnet/556995/image3.png

In BundleConfig.cs, add the JS files you want bundle into a single entity in to the bundles collection. In the below code we are combining all the javascript JS files which exist in the Scripts folder as a single unit in to the bundle collection.

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bundles.Add(new ScriptBundle("~/Scripts/MyScripts").Include(

"~/Scripts/*.js"));

Below is how your BundleConfig.cs file will look like:

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public class BundleConfig

{

public static void RegisterBundles(BundleCollection bundles)

{

bundles.Add(new ScriptBundle("~/Scripts/MyScripts").Include(

"~/Scripts/*.js"));

BundleTable.EnableOptimizations = true;

}

Once you have combined your scripts into one single unit we then to include all the JS files into the view using the below code. The below code needs to be put in the ASPX or Razor view.

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<%= Scripts.Render("~/Scripts/MyScripts") %>

If you now see your page requests you would see that script request is combined into one request.

http://www.codeproject.com/KB/aspnet/556995/image4.png

How can you test bundling in debug mode?

If you are in a debug mode you need to set EnableOptimizations to true in the bundleconfig.cs file or else you will not see the bundling effect in the page requests.

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BundleTable.EnableOptimizations = true;

Explain minification and how to implement it

Minification reduces the size of script and CSS files by removing blank spaces , comments etc. For example below is a simple javascript code with comments.

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// This is test

var x = 0;

x = x + 1;

x = x * 2;

After implementing minification the JavaScript code looks like below. You can see how whitespaces and comments are removed to minimize file size, thus increasing performance.

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var x=0;x=x+1;x=x*2;

How do we implement minification?

When you implement bundling, minification is implemented by itself. In other words the steps to implement bundling and minification are the same.

Explain Areas in MVC?

Areas help you to group functionalities in to independent modules thus making your project more organized. For example in the below MVC project we have four controller classes and as time passes by if more controller classes are added it will be difficult to manage. In bigger projects you will end up with 100’s of controller classes making life hell for maintenance.

http://www.codeproject.com/KB/aspnet/556995/MVCArea1.jpg

If we can group controller classes in to logical section like “Invoicing” and “Accounting” that would make life easier and that’s what “Area” are meant to.

http://www.codeproject.com/KB/aspnet/556995/MVCArea2.png

You can add an area by right clicking on the MVC solution and clicking on “Area” menu as shown in the below figure.

http://www.codeproject.com/KB/aspnet/556995/MVCArea3.png

In the below image we have two “Areas” created “Account” and “Invoicing” and in that I have put the respective controllers. You can see how the project is looking more organized as compared to the previous state.

http://www.codeproject.com/KB/aspnet/556995/MVCArea4.png

Explain the concept of View Model in MVC?

A view model is a simple class which represents data to be displayed on the view.

For example below is a simple customermodel object with “CustomerName” and “Amount” property.

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CustomerViewModel obj = new CustomerViewModel();

obj.Customer.CustomerName = "Shiv";

obj.Customer.Amount = 1000;

But when this “Customer” model object is displayed on the MVC view it looks something as shown in the below figure. It has “CustomerName” , “Amount” plus “Customer Buying Level” fields on the view / screen. “Customer buying Level” is a color indicationwhich indicates how aggressive the customer is buying.

“Customer buying level” color depends on the value of the “Amount property. If the amount is greater than 2000 then color is red , if amount is greater than 1500 then color is orange or else the color is yellow.

In other words “Customer buying level” is an extra property which is calculated on the basis of amount.

http://www.codeproject.com/KB/aspnet/556995/10_image.png

So the Customer viewmodel class has three properties

· “TxtCustomerName” textbox takes data from “CustomerName” property as it is.

· “TxtAmount” textbox takes data from “Amount” property of model as it is.

· “CustomerBuyingLevelColor” displays color value depending on the “Amount “ value.

Customer Model	Customer ViewModel
CustomerName	TxtCustomerName
Amount	TxtAmount
	CustomerBuyingLevelColor

What kind of logic view model class will have?

As the name says view model this class has the gel code or connection code which connects the view and the model.

So the view model class can have following kind of logics:-

· Color transformation logic: - For example you have a “Grade” property in model and you would like your UI to display “red” color for high level grade, “yellow” color for low level grade and “green” color of ok grade.

· Data format transformation logic :-Your model has a property “Status” with “Married” and “Unmarried” value. In the UI you would like to display it as a checkbox which is checked if “married” and unchecked if “unmarried”.

· Aggregation logic: -You have two differentCustomer and Address model classes and you have view which displays both “Customer” and “Address” data on one go.

· Structure downsizing: - You have “Customer” model with “customerCode” and “CustomerName” and you want to display just “CustomerName”. So you can create a wrapper around model and expose the necessary properties.

How can we use two ( multiple) models with a single view?

Let us first try to understand what the interviewer is asking. When we bind a model with a view we use the model dropdown as shown in the below figure. In the below figure we can only select one model.

http://www.codeproject.com/KB/aspnet/556995/Display.png

But what if we want to bind “Customer” as well as “Order” class to the view.

For that we need to create a view model which aggregates both the classes as shown in the below code. And then bind that view model with the view.

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public class CustOrderVM

{

public Customer cust = new Customer();

public Order Ord = new Order();

}

In the view we can refer both the model using the view model as shown in the below code.

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<%= model.cust.Name %>

<%= model.Ord.Number %>

Explain the need of display mode in MVC?

Display mode displays views depending on the device the user has logged in with. So we can create different views for different devices anddisplay mode will handle the rest.

For example we can create a view “Home.aspx” which will render for the desktop computers andHome.Mobile.aspx for mobile devices. Now when an end user sends a request to the MVC application, display mode checks the “user agent” headers and renders the appropriate view to the device accordingly.

http://www.codeproject.com/KB/aspnet/556995/DisplayMode.jpg

Explain MVC model binders?

Model binder maps HTML form elements to the model. It acts like a bridge between HTML UI and MVC model. Many times HTML UI names are different than the model property names. So in the binder we can write the mapping logic between the UI and the model.

http://www.codeproject.com/KB/aspnet/556995/form.png

Explain the concept of MVC Scaffolding?

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Note :- Do not get scared with the word. Its actually a very simple thing.

Scaffolding is a technique in which the MVC template helps to auto-generate CRUD code. CRUD stands for create, read, update and delete.

So to generate code using scaffolding technique we need to select one of the types of templates (leave the empty one).

http://www.codeproject.com/KB/aspnet/556995/m1.png

For instance if you choose “using Entity framework” template the following code is generated.

http://www.codeproject.com/KB/aspnet/556995/m2.png

It creates controller code, view and also table structure as shown in the below figure.

http://www.codeproject.com/KB/aspnet/556995/m3.png

What does scaffolding use internally to connect to database?

It uses Entity framework internally.

How can we do exception handling in MVC?

In the controller you can override the “OnException” event and set the “Result” to the view name which you want to invoke when error occurs. In the below code you can see we have set the “Result” to a view named as “Error”.

We have also set the exception so that it can be displayed inside the view.

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public class HomeController : Controller

{

protected override void OnException(ExceptionContext filterContext)

{

Exception ex = filterContext.Exception;

filterContext.ExceptionHandled = true;

var model = new HandleErrorInfo(filterContext.Exception, "Controller","Action");

filterContext.Result = new ViewResult()

{

ViewName = "Error",

ViewData = new ViewDataDictionary(model)

};

}

To display the above error in view we can use the below code

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@Model.Exception;

Please do read this blog which has detailed steps of how model binders can be created using “IModelBinder” interface: - Explain MVC model Binders?

What are the 3 main components of an ASP.NET MVC application?
1. M - Model
2. V - View
3. C - Controller

In which assembly is the MVC framework defined?
System.Web.Mvc

Is it possible to combine ASP.NET webforms and ASP.MVC and develop a single web application?
Yes, it is possible to combine ASP.NET webforms and ASP.MVC and develop a single web application.

What does Model, View and Controller represent in an MVC application?
Model: Model represents the application data domain. In short the applications business logic is contained with in the model.

View: Views represent the user interface, with which the end users interact. In short the all the user interface logic is contained with in the UI.

Controller: Controller is the component that responds to user actions. Based on the user actions, the respective controller, work with the model, and selects a view to render that displays the user interface. The user input logic is contained with in the controller.

What is the greatest advantage of using asp.net mvc over asp.net webforms?
It is difficult to unit test UI with webforms, where views in mvc can be very easily unit tested.

Which approach provides better support for test driven development - ASP.NET MVC or ASP.NET Webforms?
ASP.NET MVC

What are the advantages of ASP.NET MVC?
1. Extensive support for TDD. With asp.net MVC, views can also be very easily unit tested.
2. Complex applications can be easily managed
3. Seperation of concerns. Different aspects of the application can be divided into Model, View and Controller.
4. ASP.NET MVC views are light weight, as they donot use viewstate.

Is it possible to unit test an MVC application without running the controllers in an ASP.NET process?
Yes, all the features in an asp.net MVC application are interface based and hence mocking is much easier. So, we don't have to run the controllers in an ASP.NET process for unit testing.

Is it possible to share a view across multiple controllers?
Yes, put the view into the shared folder. This will automatically make the view available across multiple controllers.

What is the role of a controller in an MVC application?
The controller responds to user interactions, with the application, by selecting the action method to execute and alse selecting the view to render.

Where are the routing rules defined in an asp.net MVC application?
In Application_Start event in Global.asax

Name a few different return types of a controller action method?
The following are just a few return types of a controller action method. In general an action method can return an instance of a any class that derives from ActionResult class.
1. ViewResult
2. JavaScriptResult
3. RedirectResult
4. ContentResult
5. JsonResult

What is the significance of NonActionAttribute?
In general, all public methods of a controller class are treated as action methods. If you want prevent this default behaviour, just decorate the public method with NonActionAttribute.

What is the significance of ASP.NET routing?
ASP.NET MVC uses ASP.NET routing, to map incoming browser requests to controller action methods. ASP.NET Routing makes use of route table. Route table is created when your web application first starts. The route table is present in the Global.asax file.

What are the 3 segments of the default route, that is present in an ASP.NET MVC application?
1st Segment - Controller Name
2nd Segment - Action Method Name
3rd Segment - Parameter that is passed to the action method

Example: http://pragimtech.com/Customer/Details/5
Controller Name = Customer
Action Method Name = Details
Parameter Id = 5

ASP.NET MVC application, makes use of settings at 2 places for routing to work correctly. What are these 2 places?
1. Web.Config File : ASP.NET routing has to be enabled here.
2. Global.asax File : The Route table is created in the application Start event handler, of the Global.asax file.

What is the adavantage of using ASP.NET routing?
In an ASP.NET web application that does not make use of routing, an incoming browser request should map to a physical file. If the file does not exist, we get page not found error.

An ASP.NET web application that does make use of routing, makes use of URLs that do not have to map to specific files in a Web site. Because the URL does not have to map to a file, you can use URLs that are descriptive of the user's action and therefore are more easily understood by users.

What are the 3 things that are needed to specify a route?
1. URL Pattern - You can include placeholders in a URL pattern so that variable data can be passed to the request handler without requiring a query string.
2. Handler - The handler can be a physical file such as an .aspx file or a controller class.
3. Name for the Route - Name is optional.

Is the following route definition a valid route definition?
{controller}{action}/{id}
No, the above definition is not a valid route definition, because there is no literal value or delimiter between the placeholders. Therefore, routing cannot determine where to separate the value for the controller placeholder from the value for the action placeholder.

What is the use of the following default route?
{resource}.axd/{*pathInfo}
This route definition, prevent requests for the Web resource files such as WebResource.axd or ScriptResource.axd from being passed to a controller.

What is the difference between adding routes, to a webforms application and to an mvc application?
To add routes to a webforms application, we use MapPageRoute() method of the RouteCollection class, where as to add routes to an MVC application we use MapRoute() method.

How do you handle variable number of segments in a route definition?
Use a route with a catch-all parameter. An example is shown below. * is referred to as catch-all parameter.
controller/{action}/{*parametervalues}

What are the 2 ways of adding constraints to a route?
1. Use regular expressions
2. Use an object that implements IRouteConstraint interface

Give 2 examples for scenarios when routing is not applied?
1. A Physical File is Found that Matches the URL Pattern - This default behaviour can be overriden by setting the RouteExistingFiles property of the RouteCollection object to true.
2. Routing Is Explicitly Disabled for a URL Pattern - Use the RouteCollection.Ignore() method to prevent routing from handling certain requests.

What is the use of action filters in an MVC application?
Action Filters allow us to add pre-action and post-action behavior to controller action methods.

If I have multiple filters impleted, what is the order in which these filters get executed?
1. Authorization filters
2. Action filters
3. Response filters
4. Exception filters

What are the different types of filters, in an asp.net mvc application?
1. Authorization filters
2. Action filters
3. Result filters
4. Exception filters

Give an example for Authorization filters in an asp.net mvc application?
1. RequireHttpsAttribute
2. AuthorizeAttribute

Which filter executes first in an asp.net mvc application?
Authorization filter

What are the levels at which filters can be applied in an asp.net mvc application?
1. Action Method
2. Controller
3. Application
[b]Is it possible to create a custom filter?[/b]
Yes

What filters are executed in the end?
Exception Filters

Is it possible to cancel filter execution?
Yes

What type of filter does OutputCacheAttribute class represents?
Result Filter

What are the 2 popular asp.net mvc view engines?
1. Razor
2. .aspx

What symbol would you use to denote, the start of a code block in razor views?
@

What symbol would you use to denote, the start of a code block in aspx views?
<%= %>

In razor syntax, what is the escape sequence character for @ symbol?
The escape sequence character for @ symbol, is another @ symbol

When using razor views, do you have to take any special steps to proctect your asp.net mvc application from cross site scripting (XSS) attacks?
No, by default content emitted using a @ block is automatically HTML encoded to protect from cross site scripting (XSS) attacks.

When using aspx view engine, to have a consistent look and feel, across all pages of the application, we can make use of asp.net master pages. What is asp.net master pages equivalent, when using razor views?
To have a consistent look and feel when using razor views, we can make use of layout pages. Layout pages, reside in the shared folder, and are named as _Layout.cshtml

What are sections?
Layout pages, can define sections, which can then be overriden by specific views making use of the layout. Defining and overriding sections is optional.

What are the file extensions for razor views?
1. .cshtml - If the programming lanugaue is C#
2. .vbhtml - If the programming lanugaue is VB

How do you specify comments using razor syntax?
Razor syntax makes use of @* to indicate the begining of a comment and *@ to indicate the end. An example is shown below.
@* This is a Comment *@

Implementing the Repository and Unit of Work Patterns in an ASP.NET MVC Application

The Contoso University sample web application demonstrates how to create ASP.NET MVC 4 applications using the Entity Framework 5 Code First and Visual Studio 2012. For information about the tutorial series, see the first tutorial in the series. You can start the tutorial series from the beginning or download a starter project for this chapter and start here.

If you run into a problem you can’t resolve, download the completed chapter and try to reproduce your problem. You can generally find the solution to the problem by comparing your code to the completed code. For some common errors and how to solve them, seeErrors and Workarounds.

In the previous tutorial you used inheritance to reduce redundant code in the Student and Instructor entity classes. In this tutorial you'll see some ways to use the repository and unit of work patterns for CRUD operations. As in the previous tutorial, in this one you'll change the way your code works with pages you already created rather than creating new pages.

The Repository and Unit of Work Patterns

The repository and unit of work patterns are intended to create an abstraction layer between the data access layer and the business logic layer of an application. Implementing these patterns can help insulate your application from changes in the data store and can facilitate automated unit testing or test-driven development (TDD).

In this tutorial you'll implement a repository class for each entity type. For the Student entity type you'll create a repository interface and a repository class. When you instantiate the repository in your controller, you'll use the interface so that the controller will accept a reference to any object that implements the repository interface. When the controller runs under a web server, it receives a repository that works with the Entity Framework. When the controller runs under a unit test class, it receives a repository that works with data stored in a way that you can easily manipulate for testing, such as an in-memory collection.

Later in the tutorial you'll use multiple repositories and a unit of work class for the Course and Department entity types in the Course controller. The unit of work class coordinates the work of multiple repositories by creating a single database context class shared by all of them. If you wanted to be able to perform automated unit testing, you'd create and use interfaces for these classes in the same way you did for the Student repository. However, to keep the tutorial simple, you'll create and use these classes without interfaces.

The following illustration shows one way to conceptualize the relationships between the controller and context classes compared to not using the repository or unit of work pattern at all.

Code-first vs Model/Database-first

Database first and model first has no real differences. Generated code are the same and you can combine this approaches. For example, you can create database using designer, than you can alter database using sql script and update your model.

When you using code first you can't alter model without recreation database and losing all data. IMHO, this limitation is very strict and does not allow to use code first in production. This will be addressed in upcoming Microsoft Code First Migrations. But for now it is not truly usable.

Second minor disadvantage of code first is that model builder require privileges on master database. This doesn't affect you if you using SQL Server Compact database or if you control database server.

Advantage of code first is very clean and simple code. You have full control of this code and can easily modify and use it as your view model.

I can recommend to use code first approach when you creating simple standalone application without versioning and using model\database first in projects that requires modification in production.

Code first

· Very popular because hardcore programmers don't like any kind of designers and defining mapping in EDMX xml is too complex.

· Full control over the code (no autogenerated code which is hard to modify).

· General expectation is that you do not bother with DB. DB is just a storage with no logic. EF will handle creation and you don't want to know how it do the job.

· Manual changes to database will be most probably lost because your code defines the database.

Database first

· Very popular if you have DB designed by DBAs, developed separately or if you have existing DB.

· You will let EF create entities for you and after modification of mapping you will generate POCO entities.

· If you want additional features in POCO entities you must either T4 modify template or use partial classes.

· Manual changes to the database are possible because the database defines your domain model. You can always update model from database (this feature works quite good).

· I often use this together VS Database projects (only Premium and Ultimate version).

Model first

· IMHO popular if you are designer fan (= you don't like writing code or SQL).

· You will "draw" your model and let workflow to generate your database script and T4 template to generate yout POCO entities. You will lose part of control on both your entities and database but for small easy projects you will be very productive.

· If you want additional features in POCO entities you must either T4 modify template or use partial classes.

· Manual changes to database will be most probably lost because your model defines the database. This works better if you have Database generation power pack installed. It will allow you updating database schema (instead of recreating) or updating database projects in VS.

You won't create unit tests in this tutorial series. For an introduction to TDD with an MVC application that uses the repository pattern, see Walkthrough: Using TDD with ASP.NET MVC. For more information about the repository pattern, see the following resources:

· The Repository Pattern on MSDN.

· Using Repository and Unit of Work patterns with Entity Framework 4.0 on the Entity Framework team blog.

· Agile Entity Framework 4 Repository series of posts on Julie Lerman's blog.

· Building the Account at a Glance HTML5/jQuery Application on Dan Wahlin's blog.

Note There are many ways to implement the repository and unit of work patterns. You can use repository classes with or without a unit of work class. You can implement a single repository for all entity types, or one for each type. If you implement one for each type, you can use separate classes, a generic base class and derived classes, or an abstract base class and derived classes. You can include business logic in your repository or restrict it to data access logic. You can also build an abstraction layer into your database context class by using IDbSet interfaces there instead of DbSet types for your entity sets. The approach to implementing an abstraction layer shown in this tutorial is one option for you to consider, not a recommendation for all scenarios and environments.

What is POCO in Entity Framework?

POCOS(Plain old CLR objects) are simply entities of your Domain.Normally when we use entity framework the entities are generated automatically for you.This is great but unfortunately these entities are interspersed with database access functionality which is clearly against the SOC(Separation of concern).POCOS are simple entities without any data access functionality but still gives the capabilities all EntityObject functionalities like

· Lazy loading

· Change tracking

ur road map is to:

1. Create Models POCO

2. Create DBContext from Entity Framework

3. Create Repositories (Pattern)

4. Create UOW (Unit Of Work pattern)

· POCO Models will act as data carriers and they are independent (stand alone). These classes don't know anything about the DB.

· Entity framework is an ORM (object-relational mapper) that enables us to connect to the DB (SQL server) and map DB to our models and vice versa. We can consider it as a conduit.

· Repository pattern will expose the data retrieval, updating and saving of the data to our DB by communicating with EF (Entity Framework), and to simplify and standardize the way we work with retrieval, updating and saving.

· Unit of work pattern is to add all our repositories in one place, so we can do commit and unroll multiple changes to our repositories.

But why do we want to use all those patterns technologies? Well, the simple answer is reusability and maintainability, by decoupling the classes from their behaviour and following the single responsibility principle.

http://www.codeproject.com/KB/architecture/615499/image001_small.png

The Entity Framework enables you to use custom data classes together with your data model without making any modifications to the data classes themselves. This means that you can use "plain-old" CLR objects (POCO), such as existing domain objects, with your data model. These POCO data classes (also known as persistence-ignorant objects), which are mapped to entities that are defined in a data model, support most of the same query, insert, update, and delete behaviors as entity types that are generated by the Entity Data Model tools.

Mapping Requirements

To use POCO entities with a data model, the name of the entity type must be the same as the custom data class, and each property of the entity type must map to a public property of the custom data class. The names of the types and each of the mapped properties must be equivalent. For information on how to modify entities in a conceptual model, see How to: Create and Modify Entity Types.

Microsoft Technology Interview Questions Answers

Wednesday, 17 June 2015

MVC New Questions

Implementing the Repository and Unit of Work Patterns in an ASP.NET MVC Application

The Repository and Unit of Work Patterns

Code-first vs Model/Database-first

What is POCO in Entity Framework?

Mapping Requirements

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