HTML and CSS Reference
In-Depth Information
13.2. Client-Pull Documents
Client-pull documents are relatively easy to prepare, and you can run
them locally without requiring an HTTP server. That's because the client-
pull document has the browser request and load another document, even
if from local storage. All you need to do is embed a
<meta>
tag into the
header of your HTML or XHTML document. The special tag tells the client
browser to display the current document for a specified period of time
and then load and display an entirely new one, just as though the user
had selected the new document from a hyperlink. (Note that currently
there isn't an easy way to change just a portion of a document dynamic-
ally using client-pull, though you could use frames if you wanted a split-
screen effect.) [
<meta>, 6.8.1
]
13.2.1. Uniquely Refreshing
Client-pull dynamic documents work with all the popular browsers be-
cause they respond to a special HTTP header field called
Refresh
.
You may recall from previous discussions that whenever an HTTP server
sends a document to the client browser, it precedes the document's data
with one or more header fields. One header field, for instance, contains
a description of the document's content type, used by the browser to
decide how to display the document's contents. For example, the serv-
er precedes HTML documents with the header "Content-type: text/html,"
whose meaning should be fairly obvious.
HTML document's HTTP header by inserting a
<meta>
tag into its
<head>
.
The HTTP
Refresh
field implements client-pull dynamic HTML documents,
enabled by the
<meta>
tag format:
<meta http-equiv="Refresh" content="field value">