Web Design in a Nutshell, 3rd Edition

Generated Content

Generated content refers to content that is not in the document tree, yet is inserted in the page when it is displayed in a browser window, printed on paper, projected on a screen, read aurally, or otherwise delivered. Generated content may be specified text, images, or other media (or even the values of attributes) added before or after an element. It could be used to insert the name of the person making an edit after deleted text (del element). Used together with media-specific style sheets, generated content could be used to write out the URL after links only when the document is printed, or to say “end of table” at the end of a long table only when the document is read aurally.

There are also several properties that control counters, the mechanisms that keep track of the numbering for ordered list. Used together with generated text, it is possible to insert the word “Section” before each automatically numbered section heading. Allowing the user agent to automatically insert labels and numbers makes it easier to reorganize and relabel long documents because the numbers don’t need to be edited manually in the source.

Warning

Unfortunately, no version of Internet Explorer as of this writing supports generated content , because IE doesn’t support the :before and :after pseudoselectors . If you do specify generated content, IE will just ignore it, so it does no harm. You can begin using it immediately to provide a richer experience for users with browsers that do ...