Insight of new version of Internet Explorer IE 8

Microsoft has kept development of Internet Explorer 8 pretty quiet, but already the next major version of the most widely-used browser is available for downloading in a beta version.

While the focus of IE 7 was on security and the incorporation of a tabbed interface, version 8's main features center on stability and usability.

In terms of stability, IE 8's new automatic crash recovery feature is designed to solve one major problem that most IE users know all too well. Today, when an IE window or tab freezes or crashes, other browsers instances or tabs will likely become inoperable as well.

Automatic crash recovery does a better job of isolating instances of the IE browser - or separate tabs within the same browser - so that one stalled browser or tab can be terminated without affecting any other.

If a crash does bring down the entire browser, automatic crash recovery will attempt to restore the browser to its previous state - including all open tabs - the next time you open it.

Greater stability is fine - but ultimately boring. Luckily, that's not all IE 8 has going for it. The new browser's usability features will generate the most buzz - and are likely to tempt lots of folks to give IE 8 a try.

The new Activities feature, for instance, attempts to save you a lot of times by cutting down on the number of separate sites that you have to visit to accomplish a task. In essence, the Activities feature allows you to invoke the essential services offered on separate sites without ever leaving the page you're currently on.

Let's say, for example, that you're reading a web page and you see an address for a restaurant you'd like to visit.

Today, in order to get directions to that address, you would probably go to a mapping site and type or paste the address in and then wait for the service to provide you with a map from, say, your apartment to the restaurant.

The process is time-consuming and involves at least two browser windows and tabs, plus a bit of copying a pasting.

With IE 8's Activities feature, when you select the address, a small Activities button appears next to your mouse cursor. Clicking that Activities button brings up a context-sensitive menu of possible activities, with one of the options being the ability to map the tool using your favorite mapping site.

 
Selecting that mapping option actually invokes the mapping site in a smaller preview window inside the current browser tab.

Another Activity might pull from a review site of restaurants, allowing you to see what others have said about the restaurant without your having to visit another site.

 
The Activities feature was also created with a nod toward the growing popularity of social networking sites. Just as you can pull services from other sites, the Activities feature also allows you to push information to popular networking sites such as Facebook and Digg.

 
If you want to refer a friend to the page from which you got the address for the restaurant, for instance, you can select the Send to Facebook option on the Activities menu, and IE 8 will log you into Facebook, send the URL to Facebook, and present you with the Facebook page that allows you to add an entry.

 
A set of default Activities comes with the IE 8 browser, but you easily customise the service providers that appear on your Activities list.

 
Another time-saving feature of IE 8 is called Web Slices, which are designed to allow you to subscribe to frequently-updated portions, or "slices," of certain Web sites.

Instead of spending your time visiting three or four Web sites to get updated information from a portion of each of those sites, you would simply use Web Slices to pull that information into a single location in IE 8.

A site such as eBay, for instance, lends itself to the Web Slices feature.

Say, for instance, that you're running or watching several auctions on eBay. Typically, you would visit eBay multiple times per day to check the status of those auctions.

With Web Slices, you can instead simply subscribe to a section of the auction page by clicking a Web Slice icon that appears when you allow your mouse cursor to hover over a portion of a site that is frequently updated.

Clicking the Web Slice icon adds a new button to a Favorites bar that appears above your browser tabs. Clicking the newly-created Web Slice button on the IE 8 Favorites bar will pull the latest data from your subscribed page and show it to you in a preview window.

You can visit the page itself merely by clicking a link within the preview window.
 

As with Activities, Web Slice-enabled sections of sites must be made available by web site owners themselves. The code for doing so is fairly simple and non-proprietary, however, so it will likely simply be a matter of time before many sites become "IE 8 aware" and users start seeing the Activities and Web Slices icons as they surf their favorite sites.

 Download IE8 beta version here

HTML DOM Navigator Object

Navigator Object

The Navigator object is actually a JavaScript object, not an HTML DOM object.

The Navigator object is automatically created by the JavaScript runtime engine and contains information about the client browser.

IE: Internet Explorer, F: Firefox, O: Opera.

Navigator Object Collections

Collection	Description	IE	F	O
plugins[]	Returns a reference to all embedded objects in the document	4	1	9

Navigator Object Properties

Property	Description	IE	F	O
appCodeName	Returns the code name of the browser	4	1	9
appMinorVersion	Returns the minor version of the browser	4	No	No
appName	Returns the name of the browser	4	1	9
appVersion	Returns the platform and version of the browser	4	1	9
browserLanguage	Returns the current browser language	4	No	9
cookieEnabled	Returns a Boolean value that specifies whether cookies are enabled in the browser	4	1	9
cpuClass	Returns the CPU class of the browser's system	4	No	No
onLine	Returns a Boolean value that specifies whether the system is in offline mode	4	No	No
platform	Returns the operating system platform	4	1	9
systemLanguage	Returns the default language used by the OS	4	No	No
userAgent	Returns the value of the user-agent header sent by the client to the server	4	1	9
userLanguage	Returns the OS' natural language setting	4	No	9

Navigator Object Methods

Method	Description	IE	F	O
javaEnabled()	Specifies whether or not the browser has Java enabled	4	1	9
taintEnabled()	Specifies whether or not the browser has data tainting enabled	4	1	9

 

Global Variables in JavaScript

Every tutorial that I've seen describes that to create a global variable you have to declare it outside the function.

var myvar = 5; function myFunction()    alert(myvar); // 5 }

And this is the way I've been doing it for years. The problem is, I've never been particularly happy about this. It never felt self contained. Then I thought, "Hey, why not just attach it to the window object?" I almost feel like an idiot for not having thought of this sooner and I suspect you JavaScripters out there are thinking "well, duh".

function setValue() {     window.myValue = "test"; }  function getValue() {     alert(window.myValue); // "test" (assuming setValue has run) }

A quick search via Google revealed just how "in the dark" I've been. It turns out that when a global variable is set, it's added to the window object!

var myValue; function setValue() {     myValue = "test"; }  function getValue() {     alert(window.myValue); // yup, it's "test" } Source: http://snook.ca/archives/javascript/global_variable/