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Fundamentals of Web Programming




                    Notes
                                       !
                                     Caution  If the field values are not accepted, the submit should be cancelled.
                                   The function checkForm() returns either true or false. If it returns true the form will be submitted,
                                   otherwise the submit will be cancelled:
                                   onMouseOver  and  onMouseOut
                                   onMouseOver  and  onMouseOut  are  often  used  to  create  “animated”  buttons.


                                          Example: Below is an example of an onMouseOver event. An alert box appears when an
                                   onMouseOver event is detected:

                                   <a href=”a.html” onmouseover=”alert(‘An onMouseOver event’);return false</a>



                                      Task  Compare and contrast onLoad and onUnload events.

                                   Event Association

                                   Events are associated with HTML tags. The definitions of the events described below are as
                                   follows:
                                      abort - A user action caused an abort of an image or document load.
                                      blur - A frame set, document, or form object such as a text field loses the focus for input.

                                      click - Happens when a link or image map is clicked on.
                                      change - Happens when a form field is changed by the user and it loses the focus.
                                      error - An error happened loading a image or document.
                                      focus - A frame set, document, or form object such as a text field gets the focus for input.

                                      load - The event happens when an image or HTML page has completed the load process in
                                       the browser.
                                      mouseOut - The event happens when the mouse is moved from on top of a link or image
                                       map
                                      mouseOver - The event happens when the mouse is placed on a link or image map.
                                      reset - The user reset the object which is usually a form.

                                      submit - The user submitted an object which is usually a form.
                                      unload - The object such as a framesed or HTML document was exited by the user.
                                   The events for each HTML tag are as follows:
                                      <A>

                                           click  (onClick)
                                           mouseOver (onMouseOver)
                                           mouseOut (onMouseOut)








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