HCalendar

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hCalendar (short for HTML iCalendar) is a microformat standard for displaying a semantic (X)HTML representation of iCalendar-format calendar information about an event, on web pages, using HTML classes and rel attributes.

Contents

It allows parsing tools (for example other websites, or browser add-ons [1] like Firefox's Operator extension) to extract the details of the event, and display them using some other website, index or search them, or to load them into a calendar or diary program, for instance. Multiple instances can be displayed as timelines.

Example

Consider this semi-fictional example:

   The English Wikipedia was launched    on 15 January 2001 with a party from     2-4pm at     Jimmy Wales' house     (more information).

The HTML mark-up might be:

<p>     The English Wikipedia was launched      on 15 January 2001 with a party from      2-4pm at      Jimmy Wales' house      (<ahref="http://en.wikipedia.org/wiki/History_of_Wikipedia">more information</a>) </p>

hCalendar mark-up may be added using span HTML elements and the classes vevent, summary, dtstart (start date), dtend (end date), location and url:


<pclass="vevent">     The <spanclass="summary">English Wikipedia was launched</span>      on 15 January 2001 with a party from      <abbrclass="dtstart"title="2001-01-15T14:00:00+06:00">2pm</abbr>-     <abbrclass="dtend"title="2001-01-15T16:00:00+06:00">4pm</abbr> at      <spanclass="location">Jimmy Wales' house</span>      (<aclass="url"href="http://en.wikipedia.org/wiki/History_of_Wikipedia">more information</a>) </p>

Note the use of the abbr element to contain the machine readable, ISO8601, date-time format for the start and end times.

Accessibility concerns

Concerns have been expressed [2] that, where it occurs, the use of the abbr element (using the so-called abbr-design-pattern) in the above manner causes accessibility problems, not least for users of screen readers and aural browsers. [3] The newer h-event microformat therefore uses the HTML5 element time instead:

<timeclass="dt-start"datetime="2013-06-30 12:00">30<sup>th</sup>June2013,12:00</time>

Geo

The Geo microformat is a part of the hCalendar specification, and is often used to include the coordinates of the event's location within an hCalendar.

Attributes

For a full list of attributes, see the hCalendar cheat-sheet.

Users

Notable organisations and other websites using hCalendar include:

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References

  1. ↑ Microformats.org: Browser Support for Microformats
  2. ↑ Web Standards Project, hAccessibility: Abbreviations in Microformats
  3. ↑ Microformats Wiki: Assistive Technology
  4. ↑ Microformats – Birmingham City Council
  5. ↑ Protalinski, Emil (2011-02-18). "Facebook adds hCalendar and hCard microformats to Events". ZDNet. Retrieved 24 March 2011.
  6. ↑ Official Google Maps API Blog: Microformats in Google Maps
  7. ↑ Microformats.org: Google adds support for hCalendar and hRecipe Rich Snippets
  8. ↑ Google Webmaster Tools: Rich snippets - Events
  9. ↑ David Storey – Microformats on Opera sites
  10. 1 2 3 4 5 hCalendar Examples in the wild · Microformats Wiki
  11. ↑ Wikipedia:Microformats
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