ViewBag & ViewData :

Similarities between ViewBag & ViewData :

1. Helps to maintain data when you move from controller to view.
2. Used to pass data from controller to corresponding view.
3. Short life means value becomes null when redirection occurs. This is because their goal is to provide a way to communicate between controllers and views. It’s a communication mechanism within the server call.
4.  

Difference between ViewBag & ViewData:

1. ViewData is a dictionary of objects that is derived from ViewDataDictionary class and accessible using strings as keys.
2. ViewBag is a dynamic property that takes advantage of the new dynamic features in C# 4.0.
3. ViewData requires typecasting for complex data type and check for null values to avoid error.
4. ViewBag doesn’t require typecasting for complex data type.

CREATE WCF POST Restful service

CREATE WCF POST Restful service

Introduction


In my last article to explain about WCF Restful service using HTTP Get method.  This works well as long as you are sending small data as information to the service. But if want to deliver huge data, HTTP GET Method is not a good choice.  

When i write any WCF service, i always use POST. Reason is the advantage of POST over GET. Using HTTP POST method, you can almost achieve everything which you can achieve from GET. Despite of this you will get some additional feature if use POST. We might say that "GET" is basically for just getting (retrieving) data whereas "POST" may involve anything, like storing or updating data, or ordering a product, or sending E-mail etc. 

POST

1) Easy Character Encoding using application/x-www-form-urlencoded

2) No Proxy by default so always actual data from web server. 

3) Data length can be restricted by webserver, not by browser.

GET  

1) Character encoding will reduce the amount of data that can be used because of url encoding entities (i.e. three Japanese characters are converted to this: %26%2312454%3B%26%2312455%3B%26%2312502%3B)

2) Running a http request with GET can be cached on your web browser or a configured proxy server.

3) Maximum URL length is 2,083 characters in Internet Explorer (see MaxClientRequestBuffer: Use POST instead of GET to Send Large Amounts of Data in Request)

and lot more  

Extremely long URLs are usually a mistake. URLs over 2,000 characters will not work in the most popular web browser. Sending long information via URL is not a good way of implementation and also there has many restrictions i.e. max length of URL, Information format bla bla bla. For example Internet Explorer has a limitation implemented at 2083 characters. URIs is meant to be readable not to send information. 

So if you are writing any REST service and your information is long enough, better to choose POST instead of GET method.

In this article, i am going to create WCF Restful service using POST method and access it using HTTP Request. So we will have client and server both in this example code. I am creating one service which accepts HTTP Post XML request and response request data in XML format.  

STEP-1) 

Launch Visual Studio 2010. Click FILE->NEW->PROJECT. Create new "WCF Service Application". .

STEP-2) 

Once you create the project, you can see in solution that By Default WCF service and interface file are already created. Delete By default created file as we will create our own interface and WCF service file.

STEP-3)  

Now right click on solution and create one new WCF service file. I have given name to the service file as “RestServiceImpl.svc”.

STEP-4)  

We will create two DataContract classes for request and response purpose.

RequestData will receive the request from the client and ResponseData response. One very important thing is that POST XML format to the service should be same as RequestData. So the post xml request format can be like below:  

We must have to use namespace for the data contract in POST RESTFul service, which have multiple use i.e. reflects the current version of your code. The Same namespace should use in XML to Post data. Here i have given http://www.eysnap.com/mPlayer as namespace which can be changed.

STEP-5) 

Now we will write the OperationContract in IRestServiceImpl which is an interface.  Below is the code for that. 

As we can see in above code that here, Request and Response format is XML. We can change it to JSON also by changing the WebMessageFormat  from WebMessageFormat.Xml to WebMessageFormat.Json 

STEP-6 

Implementation of Auth OperationContract in RestServiceImpl.svc.cs here.

STEP-7)  

Now let’s move to configuration part which is the last one. There will be two basic parts of the configurations file which we must have to understand.

Services 

Behaviors 

And that’s it. Our Restful WCF POST RESTful service is ready to test. SERVICE IS READY I have created one Test WebClient in C# which makes Http request with some XML data. My application is hosted on localhost and URL is http://localhost:35798/RestServiceImpl.svc/auth . I launched and invoked service using WebClient. Below is my XML response which is correct one.

Create RESTful WCF Service API : Step By Step Guide

Create RESTful WCF Service API : Step By Step Guide

Introduction
Windows Communication Foundation (WCF) is an SDK for developing and deploying services on Windows. WCF provides a runtime environment for your services, enabling you to expose CLR types as services, and to consume other services as CLR types. In this article I am going to explain you how to implement restful service API using WCF 4.0 . The Created API returns XML and JSON data using WCF attributes.

What is REST?
Based on Roy Fielding theory "Representational State Transfer (REST), attempts to codify the architectural style and design constraints that make the Web what it is. REST emphasizes things like separation of concerns and layers, statelessness, and caching, which are common in many distributed architectures because of the benefits they provide. These benefits include interoperability, independent evolution, interception, improved scalability, efficiency, and overall performance."
Actually only the difference is how clients access our service. Normally, a WCF service will use SOAP, but if you build a REST service clients will be accessing your service with a different architectural style (calls, serialization like JSON, etc).
REST uses some common HTTP methods to insert/delete/update/retrive infromation which is below:
a) GET - Requests a specific representation of a resource
b) PUT - Create or update a resource with the supplied representation
c) DELETE - Deletes the specified resource
d) POST - Submits data to be processed by the identified resource

Why and where to use REST?
Few days back i was writing a service which was suppose to access by heterogeneous language/platform/system. It can be used by iPhone, Android, Windows Mobile, .NET web application, JAVA or PHP. Using web service it was bit complex for me to expose it to everyone using uniform system. Then we decided to use REST, which was easily espoused over cloud. This was a great example which shows the capability of SIMPLE RESTful SERVICE :) . Below is some point which will help you to understand why to use the RESTful services.
1) Less overhead (no SOAP envelope to wrap every call in)
2) Less duplication (HTTP already represents operations like DELETE, PUT, GET, etc. that have to otherwise be represented in a SOAP envelope).
3) More standardized - HTTP operations are well understood and operate consistently. Some SOAP implementations can get finicky.
4) More human readable and testable (harder to test SOAP with just a browser).
5) Don't need to use XML (well you kind of don't have to for SOAP either but it hardly makes sense since you're already doing parsing of the envelope).
6) Libraries have made SOAP (kind of) easy. But you are abstracting away a lot of redundancy underneath as I have noted. Yes in theory SOAP can go over other transports so as to avoid riding atop a layer doing similar things, but in reality just about all SOAP work you'll ever do is over HTTP.

Step by step guide
Generally developer scared to use WCF because lot of confusing configuration. I will try to use minimum configuration so that it will be easier to understand for us. We will develop Restful WCS API in 6 steps. So let’s start now.

STEP:1) First of all launch Visual Studio 2010. Click FILE->NEW->PROJECT. Create new "WCF Service Application" .

STEP-2) Once you create project, you can see in solution that By Default WCF service and interface file is already created. Delete By default created file as we will create our own interface and WCF service file.

STEP-3) now Right click on solution and create one new WCF service file. I have given name to the service file as “RestServiceImpl.svc”.

STEP-4) As i explained in starting of the article that we will be writing an API which can return data in XML and JSON format, here is the interface for that. In IRestServiceImpl , add following code.

In above code, you can see two different method of IRestService which is XMLData and JSONData. XMLData Returns result in XML whereas JSONData in JSON.

STEP-5) Open the file RestServiceImpl.svc.cs and write following code over there..

STEP-6) Now let’s move to configuration part which is the last one. There will be two basic part of the configuration file which we must have to understand...

This part contains information about the End Point. below is the code detail..

This part contains details about service and endpoint behavior.

And that’s it. Our Restful WCF service is ready for test purpose.

Service Ready to Test Now
Now i launch the application in browser to see the result. I launch this service in IE and my URL is now http://localhost:35798/RestServiceImpl.svc . Now if i use http://localhost:35798/RestServiceImpl.svc/xml/123 URL, i get following response on the browser which an XML format and that was my task to achieve.

Now if i use http://localhost:35798/RestServiceImpl.svc/json/123 URL, i get following response on the browser which an XML format and that was also my task to achieve.