Make external links orange
importance: 3
Make all external links orange by altering their style property.
A link is external if:
- Its
hrefhas://in it - But doesn’t start with
http://internal.com.
Example:
<a name="list">the list</a>
<ul>
<li><a href="http://google.com">http://google.com</a></li>
<li><a href="/tutorial">/tutorial.html</a></li>
<li><a href="local/path">local/path</a></li>
<li><a href="ftp://ftp.com/my.zip">ftp://ftp.com/my.zip</a></li>
<li><a href="http://nodejs.org">http://nodejs.org</a></li>
<li><a href="http://internal.com/test">http://internal.com/test</a></li>
</ul>
<script>
// setting style for a single link
let link = document.querySelector('a');
link.style.color = 'orange';
</script>The result should be:
First, we need to find all external references.
There are two ways.
The first is to find all links using document.querySelectorAll('a') and then filter out what we need:
let links = document.querySelectorAll('a');
for (let link of links) {
let href = link.getAttribute('href');
if (!href) continue; // no attribute
if (!href.includes('://')) continue; // no protocol
if (href.startsWith('http://internal.com')) continue; // internal
link.style.color = 'orange';
}Please note: we use link.getAttribute('href'). Not link.href, because we need the value from HTML.
…Another, simpler way would be to add the checks to CSS selector:
// look for all links that have :// in href
// but href doesn't start with http://internal.com
let selector = 'a[href*="://"]:not([href^="http://internal.com"])';
let links = document.querySelectorAll(selector);
links.forEach(link => link.style.color = 'orange');