CSS: Under-utilized Content Property

#Batman {
background-color: black;
clear: both;
visibility: hidden;
content: “I’m Batman”; }  /* @CSSHumor */

Introduction

In this post, we’ll discuss about:

• (The Theory) use and importance of CSS property – content
• (The Magic) creating printable links using CSS content and pseudo-elements

If you are not interested in ‘The Theory’ which is available in almost all CSS books and web tutorials like w3schools.com, you can start with ‘The Magic’, the feature which motivated me to write this blog post.

CSS ‘content’ Property

The primary use of CSS is to describe the presentation semantics of an HTML document but, we can also use CSS for content generation. With content property, we can inject a piece of information to an existing document. We have to use content property along with pseudo-elements like :before, :after, etc.

Example

I feel the best use of content property is to inject the URL of a hyperlink next to its text content.

a:after
{
   content: "(" attr(href) ")";
}

This will inject the URL mentioned within the href tag next to each link and will be decorated with a pair of parenthesis. For detailed list of content property values, you may refer to w3Schools.com.

Create Printable Links

Before we start, let’s have a look at the below paragraph of an HTML page:

“If you want to start learning web technologies, then there is no better place than W3School to start with. For Microsoft technologies, you can get comprehensive help from MSDN. My suggestion is to follow blogs like Technology Talks, Daily Dot Net Tips, Dot Net Tricks, Kunal Chowdhury, SQL Authority etc. ”

The HTML code for this is:

Note that this HTML snippet has certain links to some other places. Now let someone want to print the page containing the above paragraph. He/she will get the print copy as the above paragraph but:

• What about the links?
• How can the user get the links for Technology Talks, Daily Dot Net Tips, Dot Net Tricks, Kunal Chowdhary, SQL Authority, etc. from the print copies?
• Is there any way that we can show links on the print copy but not in the web page?

Solution

The easiest solution is to use content property of CSS along with pseudo-element :after. And as we want the URL to be injected next to its corresponding link only in the print page and not in the page that is rendered to the browser, we need to mention media type as ‘print’. So code view of the final document may look like:

<style media="print">
    a:after {
      content: "(" attr(href) ")";
    }
</style>
<div>If you want to start learning web technologies then there is no better place than
 <a href="http://www.w3schools.com/">W3School</a> to start with.For Microsoft technologies
 you can get comprehensive help from 
 <a href="http://msdn.microsoft.com/en-US/">MSDN</a>.
 My suggestion is to follow blogs like 
 <a href="http://suvendugiri.wordpress.com/">
 Technology Talks</a>, 
 <a href="http://dailydotnettips.com/">Daily Dot Net Tips</a>,
 <a href="http://www.abhisheksur.com/">Dot Net Tricks</a>, 
 <a href="http://www.kunal-chowdhury.com/">
 Kunal Chowdhury</a>, 
 <a href="http://blog.sqlauthority.com/">SQL Authority</a> etc.</div>

Live Demo

You can view the live demo here. To spot the differences, just view the print preview in Google Chrome or, you can take a printout of it.

Conclusion

Now, we are able to do the magic with which we can create better web pages with links for both kind of users, i.e., online users and offline users (with printed material).

Hopefully, you have enjoyed reading this post.
I’ll love to read feedback from you.
Thanks !

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