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Fundamentals of Web Programming                                Pawan Kumar, Lovely Professional University




                    Notes                    Unit 11: Handling Events Using JavaScript


                                     CONTENTS
                                     Objectives
                                     Introduction

                                     11.1 Working on Event
                                          11.1.1  onLoad and onUnload
                                          11.1.2  onFocus, onBlur and onChange

                                          11.1.3  onSubmit
                                          11.1.4  onMouseOver and onMouseOut
                                     11.2 onClick Event Handler and onSelect Event Handler
                                          11.2.1  onClick Event Handler
                                          11.2.2  onSelect Event Handler

                                     11.3 Summary
                                     11.4 Keywords
                                     11.5 Review Questions

                                     11.6 Further Readings
                                   Objectives


                                   After studying this unit, you will be able to:
                                      Explain the working of event
                                      Describe different events in JavaScript

                                   Introduction

                                   By using JavaScript, we have the ability to create dynamic web pages. Events are actions that can
                                   be detected by JavaScript.
                                   Every element on a web page has certain events which can trigger a JavaScript. For example, we
                                   can use the onClick event of a button element to indicate that a function will run when a user
                                   clicks on the button. We define the events in the HTML tags.

                                   Examples of events:
                                      A mouse click
                                      A web page or an image loading
                                      Mousing over a hot spot on the web page

                                      Selecting an input field in an HTML form
                                      Submitting an HTML form
                                      A keystroke





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