HTML5 for Applications: The Fourth IE10 Platform Preview

November 29th, 2011

An updated platform preview of IE10 for the
Windows Developer Preview
is now available for
. This IE10 preview adds even more support for HTML5 technologies,
enabling richer Web applications with significantly improved performance. IE10’s
hardware acceleration of technologies like SVG, CSS3 transforms and animations delivers
faster rendering than other browsers, as highlighted in this short video.

With this fourth Platform Preview, developers can start
working with more site-ready HTML5 technologies. You can read the full list
in the IE10 developer guide. Here are a few highlights:

  • Cross-Origin Resource Sharing (CORS) for safe use of XMLHttpRequest across domains.
  • File API Writer support for blobBuilder allowing manipulation of large binary objects
    in script in the browser.
  • Support for JavaScript typed arrays for efficient storage and manipulation of typed
  • CSS user-select property to control how end-users select elements in a Web page
    or application.
  • Support for HTML5 video text captioning, including time-code, placement, and captioning
    file formats.

These foundational capabilities are what developers building native applications
depend on: working with binary data and files, controlling selection and hit testing
in application UI, and providing accessible video content with captioning. The features
in this platform preview are available to Web pages now, and will be available to
Metro style applications in Windows 8.

Building HTML5 Applications

This IE10 preview supports CORS (cross
origin resource sharing
) to allow developers to use XMLHttpRequest to safely
request, share, and move data across applications on different domains. This is
a common pattern developers use to bring data and services together from different
applications. In this
test drive demo
, you can see how CORS is used along with XMLHttpRequest,
the File API, and HTML5 progress control to deliver a smooth experience for uploading
multiple files to a service on another domain.

Click here to see
CORS used with XMLHttpRequest to upload files across domains.

Having the ability to work with binary data and files enables developers to build
new kinds of applications and experiences on the Web. This IE10 preview supports
blobBuilder from File API: Writer
for working with large binary objects (blobs) and JavaScript typed arrays. In this test drive demo,
you can see how different file types, including file types which are not natively
supported in the browser like PCX files can be read, rendered, and even have their
internal contents displayed.

Click here to
see how JavaScript typed arrays used with File APIs to read and view binary files.

As developers build more sophisticated applications on the Web, they have more need
for precise control over how end-users select parts of the page. With CSS user select
support in IE10, developers can specify which elements in their page can be selected
by the consumer when using their applications. In this
this test drive demo
, you can see how selection control is applied in a
sample blog application using the user-select property in a CSS rule.

Click here to
try CSS user-select to control end-user Web page selection.

Improving Same Markup for HTML5

We continue to contribute to the
test suites
under development at the HTML5 standards bodies, submitting
118 new tests
to them, to further the goal of interoperability and same
markup. You can view them at the IE Test Center as well. We strongly encourage all
developers to write for HTML5 standards first by always using the HTML5 doc type
<!DOCTYPE html> in your pages.

IE10 Preview 4 introduces an updated
quirks mode
that is more consistent and interoperable with the way quirks modes
works in other browsers like Firefox, Chrome, Safari, and Opera. This updated quirks
mode supports quirks for page layout, while allowing use of more up-to-date standards
features like HTML5 elements for audio, video, canvas, and more.

You can find a full list of new functionality available to developers in the IE10
developer guide here.
Download the Windows 8 developer preview
to try this update to IE10. We look forward to continued engagement with the developer
community and your feedback on Connect.

—Rob Mauceri, Group Program Manager, Internet Explorer