ain article: Internet Explorer 9
According to Microsoft, Internet Explorer 9, currently in development, will have complete or nearly complete support for all CSS 3 selectors, border-radius CSS 3 property, faster JavaScript, embedded ICC v2 or v4 color profiles, and hardware accelerated rendering using Direct2D and DirectWrite. Microsoft has confirmed that WOFF will also be supported.[42] WOFF is "a strong favorite" for standardization by the W3C Web Fonts Working Group.[43]
Microsoft has continued to downplay the importance of passing the Acid3 test,[44] but speculation that IE9 would support the SVG W3C recommendation was ignited when Microsoft announced they had joined the SVG Working Group.[45] At MIX 10, the first IE9 Platform Preview was released, which featured support for CSS3 and SVG, a new JavaScript engine called Chakra, and a score of 55/100 on the Acid3 test, up from 20/100 for IE8. On May 5, 2010, the second IE9 Platform Preview was released, which featured a score of 68/100 on the Acid3 test and faster performance on the WebKit SunSpider JavaScript benchmark than the first IE9 Platform Preview. On June 23, 2010, the third IE9 Platform Preview was released, which scores 83/100 on the Acid3 test and introduced support for , , and elements and WOFF. On August 4, 2010, the fourth IE9 Platform Preview was released, which features a score of 95/100 on the Acid3 test and a faster JavaScript engine than the third IE9 Platform Preview. The final build of IE9 is expected to be released in 2011. Support for the HTML5 video and audio tags was also promised.[46][47] Some industry experts predict that Microsoft will release IE9 as a major out-of-band version that is not tied to any particular version of Windows.[48] According to the Internet Explorer 9 Test Drive page, the system requirements for IE9 are Windows Vista SP2 (with Platform Upgrade and IE8) or Windows 7.[49]
Features
Internet Explorer has been designed to view a broad range of web pages and to provide certain features within the operating system, including Microsoft Update. During the heyday of the browser wars, Internet Explorer superseded Netscape only when it caught up technologically to support the progressive features of the time.[50]
- Standards support
Internet Explorer, using the Trident layout engine:
- supports HTML 4.01, CSS Level 1, XML 1.0 and DOM Level 1, with minor implementation gaps.
- fully supports XSLT 1.0 as well as an obsolete Microsoft dialect of XSLT often referred to as WD-xsl, which was loosely based on the December 1998 W3C Working Draft of XSL. Support for XSLT 2.0 lies in the future: semi-official Microsoft bloggers have indicated that development is underway, but no dates have been announced.
- partially supports CSS Level 2 and DOM Level 2, with major implementation gaps and conformance issues. Almost full conformance to CSS 2.1 has been added in the Internet Explorer 8 release.[51][52]
- does not support XHTML, though it can render XHTML documents authored with HTML compatibility principles and served with a
text/htmlMIME-type. - does not support SVG in any version.
Internet Explorer uses DOCTYPE sniffing to choose between standards mode and a "quirks mode" in which it deliberately mimicks nonstandard behaviors of old versions of MSIE for HTML and CSS rendering on screen (Internet Explorer always uses standards mode for printing). It also provides its own dialect of ECMAScript called JScript.
Internet Explorer has been subjected to criticism by W3C over its limited support for SVG promoted by W3C.[53]
- Non-standard extensions
Internet Explorer has introduced an array of proprietary extensions to many of the standards, including HTML, CSS and the DOM. This has resulted in a number of web pages that appear broken in standards-compliant web browsers and has introduced the need for a "quirks mode" to allow for rendering improper elements meant for Internet Explorer in these other browsers.
Internet Explorer has introduced a number of extensions to JScript which have been adopted by other browsers. These include the innerHTML property, which returns the HTML string within an element; the XMLHttpRequest object, which allows the sending of HTTP request and receiving of HTTP response; and the designMode attribute of the contentDocument object, which enables rich text editing of HTML documents. Some of these functionalities were not possible until the introduction of the W3C DOM methods. Its Ruby character extension to HTML is also accepted as a module in W3C XHTML 1.1, though it is not found in all versions of W3C HTML.
Microsoft submitted several other features of IE for consideration by the W3C for standardization. These include the 'behavior' CSS property, which connects the HTML elements with JScript behaviors (known as HTML Components, HTC); HTML+TIME profile, which adds timing and media synchronization support to HTML documents (similar to the W3C XHTML+SMIL); and the VML vector graphics file format. However, all were rejected, at least in their original forms. VML was, however, subsequently combined with PGML (proposed by Adobe and Sun), resulting in the W3C-approved SVG format, currently one of the few vector image formats being used on the web, and which IE is now virtually unique in not supporting.[54]
Other non-standard behaviors include: support for vertical text, but in a syntax different from W3C CSS3 candidate recommendation; Support for a variety of image effects[55] and page transitions, which are not found in W3C CSS; Support for obfuscated script code, in particular JScript.Encode().[56] Support for embedding EOT fonts in web pages.[57]
- Favicon
The favicon (short for "favorites icon") introduced by Internet Explorer is now also supported and extended in other browsers. It allows web pages to specify a 16-by-16 pixel image for use in bookmarks. In IE, support was, and still is, provided only for the native Windows ICO format; in other browsers it has now been extended to other types of images such as PNG and GIF.
- Usability and accessibility
Internet Explorer makes use of the accessibility framework provided in Windows. Internet Explorer is also a user interface for FTP, with operations similar to that of Windows Explorer (although this feature requires a shell window to be opened in recent versions of the browser, rather than natively within the browser). Visual Basic for Applications (VBA) is not supported, but available via extension (iMacros). Recent versions feature pop-up blocking and tabbed browsing. Tabbed browsing can also be added to older versions by installing Microsoft's MSN Search Toolbar or Yahoo's Yahoo Toolbar.
- Cache
Internet Explorer caches visited content in the Temporary Internet Files folder to allow quicker access (or offline access) to previously visited pages. The content is indexed in a database file, known as Index.dat. Multiple Index.dat files exist which index different content - visited content, web feeds, visited URLs, cookies etc.[58]
Prior to IE7, clearing the cache used to clear the index but the files themselves were not reliably removed, posing a potential security and privacy risk. In IE7 and later, when the cache is cleared, the cache files are more reliably removed, and the index.dat file is overwritten with null bytes.
- Group Policy
Internet Explorer is fully configurable using Group Policy. Administrators of Windows Server domains can apply and enforce a variety of settings that affect the user interface (such as disabling menu items and individual configuration options), as well as underlying security features such as downloading of files, zone configuration, per-site settings, ActiveX control behavior and others. Policy settings can be configured for each user and for each machine. Internet Explorer also supports Integrated Windows Authentication.
Author: MircosoftDate: 2010-8-4
Size: 16 MB
License: Freeware
Requires: Win7/Vista
0 comments:
Post a Comment