ASP.NET Page Life Cycle Events

—PreInit

—Init

—PreLoad

—Load

—Control Events

—PreRender

—SaveViewState

—Render

—Unload 

—PreInit()

—This is the first event which raised  in asp.net page lifecycle

—Check for Request is for Post Back or not.

—All dynamic control need to be created

—Theme Change, Master Page Set at runtime

—Init()

—Raised after all controls have been initialized

—Build up a tree of controls from the ASPX file

—Turn on view state monitoring – any changes in control will be tracked by View State for future.

—PreLoad()

—Load view state data for page and controls

—Load Postback data if needed

—We can process any kind operation that need to perform before page load

—Load()

—OnLoad methods control called for each and every control

—We can create the connection initialization for any kind of external source like database connection

—We can also set the control properties

—Control Events

—If this is an postback request , Corresponding events will triggered. Like, if the post back is happing for button click, then Button_Click Event will fired.

—PreRender

—Each control of the page has a PreRender event which is being invoked.

—EnsureChildControls is also being called during this events

—DataBind method for all control has also been called

If we want to change any thing to any control this is the last event where we can do because after the pageRender starts 

—SaveViewState

—ViewState Monitoring is turned off as here all the ViewState Data need to be saved.

—View State data saved in hidden filed called _VIEWSTATE

—Render

—Pages calls the Render method for each and every control.

—Text writer that writes the output to the as output stream

—Output steam set to the page's Response property.

—Unload

—This is the last event of asp.net page life cycle

—This ensure the Request and Response has been set to null.

—This is called only after the content of the page fully rendered and response sent to client