to Create Channels in XML
helps a user to include shortcuts to web sites. These channels notify the user
whenever any critical information has been changed in the web sites. This process
is known as Web casting or Push. Channel Definition Format developed by Microsoft
for defining channels is one of the first real time applications of XML.
is defined in a separate file whose extension is CDF. A CDF file is a pure XML
file, which contains links to HTML documents. The CDF file need not be an addition
to a web site. The site may contain a link to the CDF file.
When the user
traverses through the link a copy of the channel index is downloaded to the users
machine. Also an icon is placed in the channel bar which links to the contents
of the channel at the same time.
steps to be followed in creating a channel Creation format are the following:
The contents of the channel should be determined.
· The CDF file
is written which contains the links to these contents.
· A link
should be placed in the web sites home page.
Some of the points that are
to be considered while deciding the contents of a channel are the following:
A channel should not have more than eight items.
2. Channels should be arranged
3. A channel can contain sub-channels.
4. The hierarchy
of the channels should match the hierarchy of the web site for easy maintenance.
next consideration is the ways in which the updated information about a channel
is delivered to the end user. There are three different ways in which the user
can obtain the updated information. In the first way the user can check in whenever,
with the help of the channel bar.
The second way is to notify the users
through e-mail and then load the channel whenever they want to. The third way
is that the browser can periodically check the web site for updates and download
the contents automatically.
channels using cdf document:
A CDF document is an XML document and hence follows the rules of XML only. A CDF
document begins with an XML declaration. The channel element is the root of all
CDF documents. The channel element should contain the HREF attribute, which contains
the link to the page being monitored for changes. Example for a simple CDF document:
A channel can contain a collection of other
pages that are identified by the ITEM. Each ITEM element has a corresponding HREF
attribute which identifies a page. Channels are often shown as collapsible tree
structure. To add a channel to the web browsers channel the following steps should
1. Save the (above example) lines of code in a file called
2. Open this file in windows explorer.
Once the file is
opened, a screen will be prompted. Click OK to add this channel to the channels
folder. After adding the new channel, it is then listed in the browsers channel
folder. Once after creation of the CDF file it must be made available to the end
user. An easy way to do is to link the CDF file with a standard HTML <A>
tag. An example for how it is done is given below:
<A HREF =add.cdf>Add
Home page to Channels</A>
When the user activates this link in a CDF
enabled browser such as Internet Explorer 5.0, the browser downloads this file
and adds the channel to its list of subscriptions.
Thus a channel and
each ITEM in the channel can have a title, an abstract, and up to three logos
of different sizes. These are established by giving the Channel and ITEM elements
TITLE, ABSTRACT, and LOGO.
Subscribe to our mailing list and receive new articles
through email. Keep yourself updated with latest
developments in the industry.
: We never rent, trade, or sell my email lists to
We assure that your privacy is respected
Current With the Latest Technology Developments Realted to XML. Signup for Our
Newsletter and Receive
New Articles Through Email.
: We never rent, trade, or sell our email lists to anyone. We assure that
your privacy is respected and protected.