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Für einen web browser ist ein access key or accesskey mit denen der computer user auf spezifische web page via keyboard zugreifen kann. Diese wurde 1999 eingeführt und umgesetzt für den They were introduced in 1999 and quickly achieved near-universal browser support.

In the summer of 2002, a Canadian Web Accessibility[1] consultancy did an informal survey to see if implementing accesskeys caused issues for users of adaptive technology, especially screen reading technology used by blind and low vision users. These users require numerous keyboard shortcuts to access web pages, as "pointing and clicking" a mouse is not an option for them. Their research showed that most key stroke combinations did in fact present a conflict for one or more of these technologies, and their final recommendation was to avoid using accesskeys altogether.

In XHTML 2, a revised web authoring language, the HTML Working Group of the World Wide Web Consortium deprecated the accesskey attribute in favor of the XHTML Role Access Module. However, XHTML 2 has been retired in favor of HTML 5, which (as of August 2009) continues to permit accesskeys.

Access in different Browsers

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A more complete list, which browser support the HTML Access keys are compared in the comparison of web browsers.

In most web browsers, the user invokes the access key by pressing Vorlage:Keypress (on PC) or Vorlage:Keypress (on Mac) simultaneously with the appropriate character on the keyboard.

Web Browser Modifier Effect Notes
Amaya Vorlage:Keypress or Vorlage:Keypress Adjustable in preferences
Blazer Link is activated immediately upon key press. No modifier is needed for this web browser used on mobile devices.
Google Chrome 1 Vorlage:Keypress Current stable release version 2 does not support access keys[2] (However, Chrome 3 is reported to be available and to support accesskeys again.)
Firefox 2 & 3 Vorlage:Keypress + Vorlage:Keypress Prior to version 2.0 Firefox used just Alt
Configurable via about:config
Internet Explorer Vorlage:Keypress Vorlage:Keypress + Access Key focuses on the link, but requires Vorlage:Keypress to be pressed in order to activate the link
Konqueror Vorlage:Keypress The modifier key must be released before the regular key is pressed.
Opera Vorlage:Keypress+Vorlage:Keypress The modifier key must be released before the regular key is pressed. Once the modifier key is released, browser lists the set of access keys on that page with action and user can hit the desired key. Configurable via Graphical user interface
Safari 3 Vorlage:Keypress (Vorlage:Keypress for Windows )
Safari 4 Vorlage:Keypress+Vorlage:Keypress (Vorlage:Keypress for Windows )

Multiple access keys

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If multiple identical access keys are assigned within the same document, IE will tab through them on each keypress (IE will tab backwards if Vorlage:Keypress is pressed as well). This way, links can be logically grouped in various access key rings for easier navigation. IE 4.0 only supported letters of the English alphabet as accesskeys. Firefox 2.0 will activate the last of a group of links assigned the same accesskey.

Specifying access keys

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Access keys are specified using the accesskey attribute. The value of the accesskey attribute is what the user will press in order to follow that specific link. Though the accesskey attribute sets the key that can be pressed it does not automatically notify the user of the bound access key. One convention is for the page author to show the access key value by using the '<u>' tag to underline the a letter in the link's text corresponding to the accesskey assigned. For the link below you would press Vorlage:Keypress+Vorlage:Keypress on a PC, Vorlage:Keypress+Vorlage:Keypress on a Mac (the command key can give undesired results) and Vorlage:Keypress+Vorlage:Keypress+Vorlage:Keypress on Opera to be directed to index.html.

<a href="index.html" accesskey="h">Home</a>

or to emphasize'H':

<a href="index.html" accesskey="h"><em>H</em>ome</a>

alternatively, the following CSS can be used to indicate the character:

*[accesskey]:after {content:' [' attr(accesskey) ']'}

Emphasize '<em>' isn't necessary, but can be useful to the user. It helps them identify which key to press to navigate to where they want to. Another possible way of displaying which accesskeys do what is to create a page with all the accesskeys displayed. Or the webmaster could do both.

Use of standard access key mappings

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As of 2004, a standard emerged using numbers, which promotes consistency and enables users more easily to predict keyboard shortcuts on different sites. These include, for example, 1 to go to the homepage, 4 for search, 9 for contact, and others. This scheme is now in use on popular sites such as ft.com and bbc.co.uk , as well as being built into popular message board software such as vBulletin and ultimatebb.

UK Government recommendation for access keys

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  • S - Skip navigation
  • 1 - Home page
  • 2 - What's new
  • 3 - Site map
  • 4 - Search
  • 5 - Frequently Asked Questions (FAQ)
  • 6 - Help
  • 7 - Complaints procedure
  • 8 - Terms and conditions
  • 9 - Feedback form
  • 0 - Access key details

Vorlage:Reflist

Vorlage:Web browsers {{DEFAULTSORT:Access Key}} [[Category:Keyboards (computing)]]

  1. Using Accesskeys is it worth it?:[1]
  2. Discussion on Google´s Chrome Help web page: Accesskeys are disabled in Beta 2.0.169.1