ASP.Net Development

Improve the Performance of an ASP.Net Application

• Effectively use CSS and Script files
• Images sizes
• CSS based layout
• Validate using JavaScript
• Avoid Round trips
• Use Caching
• Clear the Garbage Collection
• Avoid bulk data store on client side
• Implement Dynamic Paging
• Use Stored Procedure
• Use Dataset
• Use String Builder in place of String
• Use Server.Transfer

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What is Rendering?
Rendering refers to the process of creating a visual representation on a display surface. In the case of Web requests, the actual rendering is performed by a client's Web browser or other viewing device.
in Page Rendering All ASPX Controlls are Converted to HTML Controls ,Because Browser understand only html markup.
Render is not an event. It is a method called to generate the output to send to the client.
Render renders itself and its children. 

What is the use of @ Register directives in asp.net

@Register directive informs the compiler of any custom server control (like ajaxcontrols, usercontrol.ascx) added to the page.

Example:-

<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit"TagPrefix="ajaxToolkit" %>

What is event bubbling in Asp.Net

Handling(tracking) child controls events (only button type child controls) through parent control in data bind controls known as event bubbling.

Server controls like Datagrid, DataList, and Repeater can have other child controls inside them.

Example DataGrid can have combo box inside datagrid. These child control do not raise there events by themselves, rather they pass the event to the container parent (which can be a datagrid,

datalist, repeater), which passed to the page as "ItemCommand" event. As the child control send events to parent it is termed as event bubbling.