• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Unit 2 computer systems

Extracts from this document...


Main features of JavaScript - P3 Browser Support Control Data Validation Detecting a Users OS or Browser Browser Support To access certain content you need to have the necessary plug-in, for example to access flash content, you need to install the flash plug-in in your browser. But to use JavaScript, you don't have to use any plug-in at all. This is because all browsers have accepted JavaScript as a scripting language and so they provide integrated support for it. Control A great feature of JavaScript is the control you have over the browser. There are various things you can control such as the background colour, this feature servers more than one purpose. Most people would change the colour of a webpage just because the option is there but it can also be a huge help for people who are visually impaired. Data Validation Being able to validate a users input is another great feature of JavaScript. Most websites will have a section where you may need to input some data (contact form, registration and more) and if you were to enter your name in a section that is expecting numeric input you will get an error message. ...read more.


Image on the right shows what happens when you enter an invalid email address, the image on the left shows what happens when you enter a valid email address. Timer Design: - Separate document. Create: Header <script type="text/javascript"> function timedText() { var t1=setTimeout("document.getElementById('txt').value='1 Min!'",60000); var t2=setTimeout("document.getElementById('txt').value='2 Mins!'",120000); var t3=setTimeout("document.getElementById('txt').value='3 Mins!'",240000); } </script> Form <form> <input type="button" value="Display timed text!" onclick="timedText()" /> <input type="text" id="txt" /> </form> Test: This screenshot shows the timer in action, after every minuet (up to three minuets) the timer shows a message telling you how long you have been on that page. Implementation of Web Page Scripts in Two Different Browsers - M3 Not all browsers are able to implement scripts the same and the sear amount of browsers (and versions) makes it really hard to create a web page around a specific browser. As soon as you load a page that contains JavaScript you can see the differences in implementation between IE and FF straight away, Internet Explorer requires confirmation from you before it runs the script, Firefox on the other hand loads it right away. Yes there are a few security issues with Firefox automatically running scripts but you should never run into serious trouble. ...read more.


Buttons - Everyone loves buttons, forward, back or even change the colour. Alerts - Messages that pops up to tell your visitors important information. Prompts - Like an Alert except they want input from you. Data Validation - Make sure your viewers input is correct by validating what's been entered. Clocks - It's always nice to know how much time you have wasted. Browser and OS detection - Simply shows you your OS and Browser info. Redirecting - This page no longer in use? No problem, redirect them to the new one. These are just a few example of how you would improve/create interactivity in your webpage. Below is an example of how you would change the background colour of your site, this not only adds the interactivity of the site but also helps people who have visual impairments, I chose red, green and white <form> <INPUT type="button" value="Change to Yellow!" name="button3" onClick="document.bgColor='green'"> <br> <INPUT type="button" value="Change to Red!" name="button4" onClick="document.bgColor='red'"> <br> <INPUT type="button" value="Change back!" name="button5" onClick="document.bgColor='white'"> </form> Evaluate the impact of using CSS to control layout - D3 changing the layout of a webpage using HTML and tables can be a pain, not every browser loads them the same and breaking can occur. Fortunately when CSS was introduced ?? ?? ?? ?? ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Computer Science section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Computer Science essays

  1. Marked by a teacher

    The systems development life cycle (SDLC) is a conceptual model used in project management ...

    3 star(s)

    Dynamic System Development Method (DSDM), http://www.freetutes.com/systemanalysis/sa2-dynamic-system-development-method.html Waterfall model There are various software development approaches defined and designed which are used/employed during development process of software, these approaches are also referred as "Software Development Process Models". Each process model follows a particular life cycle in order to ensure success in process of software development.

  2. Peer reviewed

    information systems assignment 2

    4 star(s)

    by organizing the data according to a data model, this is a relational model. Spreadsheets A spreadsheet is an application used on computer to store data and information in a sufficient way. A spreadsheet is laid out and displayed with multiple cells making a grid.

  1. Business blue print document for the implementation of SAP R/3 (4.6B) payroll at Mastek ...

    Integration The Payroll component is integrated with other SAP HR components, such as Personnel Administration and Benefits. There are also interfaces to other SAP modules such as Financial Accounting and Controlling. 2.1 COMPENSATION FOR USA PAY SCALE TYPE During the discussions it was realized that across Mastek Group, the compensation

  2. Computer systems assignment 1

    a popular OS and it is free as well and let to distribute by people. The desktop is pretty much a window desktop and is also very intuitional. Linux OS supports dozens of programming languages which allows writing and coding in many ways.

  1. Computing Project

    //show this message end;//end end. unit Umenu; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls, ExtCtrls; type TFmMenu = class(TForm) BtnRegAMem: TButton; BtnRntDVD: TButton; BtnAddDVD: TButton; Label1: TLabel; BtnExt: TButton; BtnReturnDvd: TButton; BtnLoansOverdue: TButton; Image1: TImage; BtnLogin: TButton; BtnSetupUandP: TButton; procedure BtnSetupUandPClick(Sender: TObject); procedure BtnLoginClick(Sender: TObject);

  2. Control Unit, Memory Unit, and Arithmetic Logic Unit. The CPU or Central Processing ...

    this connects the musical keyboard to the processor and allows data to be passed between the instrument and the processor. b) Mouse. A mouse is a device designed to be used with a pointer on the screen. It is particularly useful because it mimics the natural human reaction of being able to point at something.

  1. With diagrams compare and contrast the relative advantages and disadvantages of digital transmission over ...

    Coaxial Cable The development of coaxial cable ("coax") as a data communications standard was largely driven by its widespread operation throughout the cable television industry. The economies of scale make it an attractive, low-cost option for computer networking, although it is more expensive than twisted pair.

  2. Free essay

    Setting up and E-Commerce Site

    * Unlimited number of products (you pay for web space separately) - This is a very useful service and means that the business has no limitations in the amount that it can sell. Therefore if the business becomes very successful and they need to expand then there are very little limitations on the quantity of products that can be displayed.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work