Skip to main content

Page life cycle of ASP.net page



The stsges of Page life cycle are as follows :
Methods Description
Page_Init Page Initialization
LoadViewState View State Loading
LoadPostData Postback Data Processing
Page_Load Page Loading
RaisePostDataChangedEvent PostBack Change Notification
RaisePostBackEvent PostBack Event Handling
Page_PreRender Page Pre Rendering Phase
SaveViewState View State Saving
Page_Render Page Rendering
Page_Unload Page Unloading

Page_Init :

The Page_Init event is the first event to be triggered in the page life cycle. In this the control tree has been created, the controls declared in the .aspx file are initialized. The viewstate is not available at this stage. We can create or re-create the controls that need to be created or re-created dynamically.

LoadViewState :

The Viewstate contains stored information that is set by the page and controls of the page. But the load view state event only occurs when the page has been posted back. Due to viewstate control's and page itself store information that is persistent among web requests. It contains the state of the controls the last time the page was processed on the server.

LoadPostData :

After viewstate is loaded the control are updated with posted values or values that are entered or changed by user.

Page_Load :

After Loadpostdata the page_load event is fired. In this event code written inside page load is executed once at the beginning of the page.

RaisePostDataChangedEvent :

In this event when user clicks submit button or any other button then it changes state of the page and the event related to that button is raised.

RaisePostBackEvent :

This methods knows which event has occurred and which related method you need to call like btnsubmit is clicked then it will call method related to it like “btnsubmit_click” to perform its functionality.

Page_PreRender :

At this stage page is prepared for Rendering and if user wants to chage anything he can change it here only as in this event viewstate is not saved and output is not rendered.

SaveViewState :

In this event values of viewstate is saved to control own viewstate collection. The resultant viewstate is serialized, hashed, base24 encoded and associated with the _viewstate hidden field.

Page_Render :

This method takes the HtmlWriter object and uses it to accumulate all HTML text to be generated for the control. For each control the page calls the render method and caches the HTML output.

Page_unload :

During this method, data can be released to free up resources on the server for other processes. Once this method is completed, the HTML is sent to the browser for client side processing.

Comments

Post a Comment

Popular posts from this blog

Scrollable GridView with Fixed Headers using jQuery Plugin

Using the same example I have created a jQuery Plugin for Scrollable GridView with Fixed header so that you can directly make a GridView scrollable.   HTML Markup < form   id ="form1"   runat ="server"> < asp : GridView   ID ="GridView1"   runat ="server"   AutoGenerateColumns   =   "false"> < Columns > < asp : BoundField   DataField   =   "ContactName"   HeaderText   =   "Contact Name"   /> < asp : BoundField   DataField   =   "City"   HeaderText   =   "City"   /> < asp : BoundField   DataField   =   "Country"   HeaderText   =   "Country"   /> Columns > asp : GridView > form >   Applying the Scrollable Grid jQuery Plugin < script   src ="Scripts/jquery-1.4.1.min.js"   type ="text/javascript"> script > < script   src ="Scripts/Scro...
Post a Comment
Read more

JQuery lightbox image slideshow gallery in asp.net

Introduction: In this article I will explain how to create lightbox image slideshow in asp.net using JQuery. Description:  In previous post I explained about  Ajax SlideshowExtender sample  to display images slideshow. Now in this article I will explain how to create lightbox image slideshow in asp.net using JQuery. In many websites generally we will see different types of slideshows like whenever we click on image that is automatically open with lightbox effect and we have a chance to see all the remaining images by press next or previous options in slideshow. All these Slideshows are implemented by using JQuery plugins. After seen those slideshows I decided to write post to use JQuery plugins to implement beautiful slideshown in asp.net.  To implement this one I am using  previous post  insert and display images from folder based on imagepath in database  because in that post I explained clearly how to insert images into our project folder a...
Post a Comment
Read more

GRIDVIEW GROUPING

When displaying data, we sometimes would like to group data for better user experience or when displaying long list of hierarchal data, we would want to display them in a tree view kind of structure. There is more than way of doing this, but I am going to explain achieving this functionality using  AJAX Collapsible Panel Extender Control . Overview: I am going to use  Adventure Works  as datasource. Every product in  Production.Product  table belongs to a product sub category. We fetch handful of products and the sub categories they belong to from the database. Our objective is to list all the available sub categories and allow user to  expand/collapse  to look/hide the list of products belonging to each subcategory. Database Connection Added following entry under  connectionStrings  element in  web.config . < add   name = "Sql"   connectionString="Data Source=(local); Initial  Catalog = AdventureWorks ...
Post a Comment
Read more