Thursday, August 22, 2013

MVC Json Hijacking By Phil Haack

I m not going to write the whole story or article from Phil Haack. This is just for my reference and may people out there who is doing similar kind of blunder in implementing data in JSON response array by exposing sensitive data .

Here is what one should be doing when returning JSON response array.

Add [AcceptVerbs(HttpVerbs.Post)] to make it http request return response type.

Why we need this , you have to take little bit extra time to read Phil's blog for more detailed.

Cross Site Request Forgery (CSRF) attack

jQuery + JSON Action Methods = Cool -Some MVC controller example

It is easy to return a JSON object instead of a view.
public JsonResult Create(string CategoryName)
    var category = new Models.Category();
    category.Name = CategoryName;
    category.URLName = CategoryName.ToLower().Replace(" ", "-");

    return Json(category);

__defineSetter__ and .__defineGetter in javascript

The definesetter and definegetter reminds of how we used look into MSIL code using disassembler tool. On Similar line in javascript the line interpreter does this.

 if (Object.prototype.__defineGetter__)
    return obj.__defineGetter__(prop, get);

 if (Object.prototype.__defineSetter__)
    return obj.__defineSetter__(prop, set);

Courtesy By

As you may have noticed, all examples here use Object.defineProperty in preference to either __defineGetter__ or __defineSetter__, using the latter two only as fallback when the former is absent. While many browsers support these methods, not all do. Object.defineProperty is the future, and it is the standard; Microsoft has even gone on the record to say that they will not implement __defineGetter__ or __defineSetter__ in IE given the existence of the standardized method (props to them for that choice, by the way). For greatest forward compatibility with all browsers, you should use Object.defineProperty if it exists, and only fall back to __define{G,S}etter__ if it does not.
In a distant future we would like to remove support for __defineGetter__ and __defineSetter__, after ES5 adoption has taken off, so as not to distract from the standardized support. The less new web developers have to know about legacy extensions superseded by standardized alternatives, the better. This action is at least several years in the future, likely longer; being able to make the change will require preparation and adjustment in anticipation of that time.


ASP.NET MVC Extensibility-Internals of Pipeline Requests.

Today I came across one good reference article in simpletalk. This article gives internal architecture of pipeline processing for MVC framework. This is something which I always feel was missing in tutorial or documentation site of Even the MVC is creating a stir in web development but too less has been revealed in terms of documentation which entails the true story of framework.

At a very high level, the lifecycle of a request in ASP.NET MVC is:
  • The browser sends the GET or POST HTTP request;
  • The request is inspected and routed to the right controller and the right action;
  • The action collects or creates the data that needs to be returned to the browser;
  • This data is passed to the view that renders the response, which is sent back to the browser.


Wednesday, August 21, 2013

DataType Conversion in MVC Razor

The following table lists some common conversion and test methods for variables.
Converts a string that represents a whole number (like "593") to an integer.
var myIntNumber = 0;
var myStringNum = "539";
    myIntNumber = myStringNum.AsInt();
Converts a string like "true" or "false" to a Boolean type.
var myStringBool = "True";
var myVar = myStringBool.AsBool();
Converts a string that has a decimal value like "1.3" or "7.439" to a floating-point number.
var myStringFloat = "41.432895";
var myFloatNum = myStringFloat.AsFloat(); 
Converts a string that has a decimal value like "1.3" or "7.439" to a decimal number. (In ASP.NET, a decimal number is more precise than a floating-point number.)
var myStringDec = "10317.425";
var myDecNum = myStringDec.AsDecimal(); 
Converts a string that represents a date and time value to the ASP.NET DateTime type.
var myDateString = "12/27/2012";
var newDate = myDateString.AsDateTime();
ToString()Converts any other data type to a string.
int num1 = 17;
int num2 = 76;
// myString is set to 1776
string myString = num1.ToString() +

Tuesday, August 20, 2013

Make MVC @helper in more organized way

Step 1 : On The Project Create a New Director App_Code
Step 2 : To App_Code Directory Add a New Razor View Page Name It Content.cshtml
Step 3 : Paste The Helper , Here You can see the Code Modifications 


@using System.web.mvc;

@helper GenerateHTMLString(string val)



Output caching in MVC

Disable MvcHandler.DisableMvcResponseHeader = true

We should place it somewhere to be executed within the Application_Start method. Additionally it makes sense to disable writing the standard MVC response header. Adding specific headers to the response is actually kind of a security issue (not a big one), since we are telling other people about the implementation of our system (here one could spy that obviously ASP.NET MVC is used).

MvcHandler.DisableMvcResponseHeader = true;
This leaves our web app behind with optimized headers .

Precompiled Your MVC View with MVCBuildView Option

The mvc razor view are non compiled markup with code behind interleaved. You'll come to know about your Razor view errors of c# only at runtime. This is area of concerns when you deployed your code in production and you're not sure if this works as expected even though look alike testing has been conducted in staging or UAT environment.
Well I'm sure we'll see this improvement in coming version of MVC framework where we will be having compile time/built time errors in IDE itself.

Now to our rescue a work around.

true in the .csproj.

See for more details.

Tuesday, August 6, 2013

Visual Studio Magazine's Moving from Partial Views to AJAX Calls

This is one of the good example of replacing partial view and load them dynamically using Jquery Ajax.
There can be scenario where we must be looking at such option.It make use of Embedded Javascript. The article also eloborate on using Json w.r.t backbone.js and knockout.js.

Monday, August 5, 2013

MVC Repository Design pattern

Its now quite long time I've been exploring various ways to code in MVC razor and I'm now quite confident to take MVC to next level. I personally feel, I m now an intermediate MVC Razor developer. The only point I was missing till now is to work on more structure architecture concerning to separate responsibility within controller and View. So far I can say I'm able to meet that. Now I can make thin controller and can make more structured and modular pattern within my code component.

Must suggest to look for repository Design pattern for MVC if you planning to develop any application using it. This is utmost important we follow right pattern and practice right at the beginning of MVC.

This goes well with IOC and dependency injection if not still you can make use of it at greater extent.

Happy coding.

Thursday, August 1, 2013

MVC- Multiple Views with Display Mode in MVC4

Another intersting white paper on MVC internals. I m just wanting them to file this references in my blog so that I can revisit them anytime at my leisure. Well If you're following my blogs you'll definately find some cool knowledge references to MVC.

Discalimer Content taken from below write up to short summary of content given.
As you know, you should also have a file named index.cshtml located under the Views/Home folder in the project. This file will provide the HTML for the browser. In the body of the Index method above you code (or better, you invoke from other components) the logic required to serve the request. If, by executing this piece of logic, data is produced which needs to be embedded in the view, then you pass this data down to the view object by adding an argument to the View method.

Now in ASP.NET MVC 4 there’s an extra piece of magic that you might not know about yet. To experience the thrill of it, you add a new file to the Views/Home folder named You can give this file any content you like; just make sure the content is different from the aforementioned index.cshtml.

Read More.

MVC Software Design-Convention Over Configuration

In recent time I was just looking for some interesting topic in MVC and I came across the interesting one. I've been using .net for10 years now but never thought of software design that are carved and paved into whole making of framework. Why I chosen .net its simple to use with no configuration unlike Java platform. More productive gain , can built website /software in less man hour as compare to Java platform. I m making a valid point here. the whole point is .net architecture and framework is based on CoC principle.

Must read this.
CoC is analogous to a math axiom—a statement that is accepted as true without requiring proof. A CoC behavior happens because the framework was coded in that way and it does not require any further ad-hoc code or configuration on the developer’s end.

MVC - Domain Model vs View Model vs Input Model

Synopsis Model

Domain Model- Is also called Entity Model or Data model. Now this domain model represents data entity that are mapped to business domain which later consumes and act as a container for presentation and vice versa.

View Model- The data are processed or referenced in presentation layer or view finds its place in View Model as a properties. Now these data can be string, data , int etc.

Input Model- This is rather confusing and we sometimes tends to term it as View Model. But these construct solely based on input data from view by end users to controller and eventually to backend. This is form post or Get or Update/Delete operations.

The below blog post entails the whole story of domain and give examples around to better understand them.
Look also for IModelBinder,Custom DefaultModelBinder and DefaultModelBinder.

MVC Post -Redirect-Get PRG Pattern

Something worth to share.If you've closely watched and noticed the page refresh /page load of MVC web then you have to understand this pattern of Post Redirect and get-ie. PRG pattern. Now once page is loaded it is method Post in which data get processed and routed back to browser. After this if  user hit f5 or page refresh then page is not post back but indeed GET which is again a safe way to load page without being refresh. This is what MVC smartly do and identify the requests.