Sharepoint 2010 (Tutorial 2) :- Create a simple web portal using sharepo...

Sharepoint 2010 (Tutorial 2 Part 2) :- Create a simple web portal using ...

Tutorial 1 :- What is sharepoint 2010 , sharepoint foundation 2010 and s...

difference between window.onload and document.ready

Document.ready() function is different from body onload() function because off 2 reasons.

1. We can have more than one document.ready() function in a page where we can have only one onload function.
2. Document.ready() function is called as soon as DOM is loaded where body.onload() function is called when everything gets loaded on the page that includes DOM, images and all associated resources of the page. 

http modules and handlers

Introduction

All requests to IIS are handled through Internet Server Application Programming Interface (ISAPI) extensions. ASP.NET has its own filter to ensure pages are processed appropriately. By default, the ASP.NET ISAPI filter (aspnet_isapi.dll) only handles ASPX, ASMX, and all other non-display file formats used by .NET and Visual Studio. However, this filter can be registered with other extensions in order to handle requests to those file types, too, but that will be covered later.

Every request flows through a number of HTTP modules, which cover various areas of the application (i.e. authentication and session intofmation). After passing through each module, the request is assigned to a single HTTP handler, which determines how the system will respond to the request. Upon completion of the request handler, the response flows back through the HTTP modules to the user.

HTTP Module

HTTP modules are executed before and after the handler and provide a method for interacting with the request. Custom modules must implement the System.Web.IHttpModule interface. Modules are typically synchronized with events of the System.Web.IHttpModule class (implemented within the Global.asax.cs or .vb file). The following consists of a list of events that should be considered when implementing your module:

BeginRequest

AuthenticateRequest

AuthorizeRequest

ResolveRequestCache

AcquireRequestState

PreRequestHandlerExecute

PostRequestHandlerExecute

ReleaseRequestState

UpdateRequestCache

EndRequest

PreSendRequestHeaders*

PreSendRequestContent*

Error*

The events identified by an asterisk (*) can occur at any time within the request; all others are listed in their calling order.

HTTP Handlers

HTTP handlers proces the request and are generally responsible for initiating necessary business logic tied to the request. Custom handlers must implement the System.Web.IHttpHandler interface. Additionally, a handler factory can be created which will analyze a request to determine what HTTP handler is appropriate. Custom handler factories implement the System.Web.IHttpHandlerFactory interface.

When to Use

Modules should be considered only when there is a need for pass-through and/or intercepting interaction with the request. Alternatively,

handlers should be put in place when there is a need to direct functional actions to one or more parts of an application. Probably the most noted use of HTTP handlers is to the FrontController pattern, which allows requests to be refactored and assigned to different components within your application without implementing such changes in every page. E.g: for images we use

Some methods, such as the PageController pattern, allow for common functionality to be reused across multiple pages by including this logic in a base System.Web.UI.Page object, and inheriting from this for every web page. 

Web Methods

Attaching the WebMethod attribute to a Public method indicates that you want the method exposed as part of the XML Web service. The WebMethod attribute tells .NET that a particular public method should be exposed as a web-callable method. The WebMethod attribute has six associated properties to document and change the behavior of your web method. They are:

1.  Description

2.  MessageName

3.  EnableSession

4.  CacheDuration

5.  TransactionOption

6.  BufferResponse

The first two properties are used to document a web method, while the others affect its behavior.