CHANNEL Element

---

Defines a channel or subchannel.

Syntax

<CHANNEL
    BASE="url"
    HREF="url"
    LASTMOD="date"
    LEVEL="n"
    PRECACHE="YES" | "NO"
>

Attributes

BASE

Base URL for the channel. This is used to resolve relative URLs specified in ITEM and CHANNEL elements contained within this channel. The BASE attribute applies to all child elements of the current channel or subchannel. This attribute supersedes the BASE value previously defined by a parent CHANNEL element, if any exists. The URL specified must end with a trailing "/", or the last word will be removed.

HREF

URL associated with the channel. The browser navigates to this location when the user activates the channel. The HREF attribute should be omitted if the CHANNEL element contains an anchor (A) as a child element.

LASTMOD

Last date/time in GMT that the page indexed by the HREF attribute was modified. GMT is Greenwich Mean Time, also known as Universal Time Coordinated (UTC). Note that the LASTMOD date/time is not necessarily your local time. This attribute allows the channel client to determine whether the content has changed since the last time it was downloaded. The item is downloaded only if the date associated with the cached item is older than the LASTMOD value in the CDF file. Additional information on optimizing channels is available in the Creating Active Channels documentation. The date format used in the LASTMOD attribute is specified in the form yyyy-mm-ddThh:mm, where:

yyyy	Specifies the year.
mm	Specifies the month (01-12).
dd	Specifies the day of the month (01-31).
hh	Specifies the hour of the day (00-23).
mm	Specifies the minutes (00-59).

LEVEL

Number of levels (or links) deep the client should "site crawl" and precache the HTML content from the URL specified in the HREF attribute. The default is zero, which specifies to only precache the URL of the CHANNEL, along with any images it uses. If the URL contains frames, the client will also retrieve all content inside the frames. By default, the maximum number of levels that can be specified for site crawling is three.

PRECACHE

If PRECACHE is omitted or set to "YES", content is downloaded only if the user has specified that channel content should be downloaded. If PRECACHE is set to "NO", content is not downloaded and the LEVEL attribute is ignored.

Element Information

Number of occurrences	Any Number
Parent elements	CHANNEL
Child elements	A, ABSTRACT, CHANNEL, ITEM, LOG, LOGIN, LOGO, LOGTARGET, SCHEDULE, SOFTPKG, TITLE
File formats supported	CDF
Requires closing tag	Yes

Remarks

The top-level channel is defined by the first occurrence of the CHANNEL element. All CHANNEL elements contained within the top-level channel represent subchannel folders that are used to create a hierarchy of channel items.

An optional SELF attribute can be added in the top-level CHANNEL to indicate the location of the CDF file to use for creating a channel subscription. Note that this attribute is unnecessary and is only supported for backward compatibility.

Example

If more than one mechanism is used to specify a URL for a channel, Internet Explorer will look for URLs in this order of precedence:

1. The HREF attribute of the CHANNEL element.

   <CHANNEL HREF="http://...">
   

2. The HREF of the anchor (A) element that is the immediate child of the CHANNEL element.

   <CHANNEL>
   	<A HREF="http://...">My Channel</A>