Page 48 - DCAP312_WEB_TECHNOLOGIES_II

Web Technologies-II Sarabjit Kumar, Lovely Professional University

Notes Unit 3: Server Controls Basic

CONTENTS

Objectives
Introduction
3.1 PostBack
3.1.1 AutoPostBack Property in ASP.NET
3.1.2 Life Cycle of a Web Page
3.2 Data Binding
3.2.1 Properties of Data Binding

3.3 Web Server Controls
3.3.1 Generalities of ASP.NET Server Controls
3.3.2 Identifying a Server Control
3.3 3 Naming Containers
3.3.4 Themeable Controls
3.3.5 Control State

3.4 Summary
3.5 Keywords
3.6 Review Questions
3.7 Further Reading

Objectives

After studying this unit, you will be able to:

• Define postback
• Explain data binding
• Understand web server controls

Introduction

HTML server controls are HTML elements containing attributes to create them noticeable to
and programmable on the server. By default, HTML elements on a Web Forms page are not
accessible to the server; they are treated as opaque text that is passed through to the browser.
However, by converting HTML elements to HTML server controls, we expose them as elements
we can program on the server. The object model for HTML server controls maps closely to that
of the corresponding elements. For example, HTML attributes are exposed in HTML server
controls as properties.
Any HTML element on a page can be converted to an HTML server control. Conversion is a
simple process involving just a few attributes. As a minimum, an HTML element is converted
to a control by the addition of the attribute RUNAT= “SERVER”. This alerts the ASP.NET
page framework during parsing that it should create an instance of the control to use during
server-side page processing. If we want to reference the control as a member within our code,
we should also assign an ID attribute to the control.

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