What do I need to escape inside the html <pre> tag

html html-encode
Alec Jacobson picture Alec Jacobson · Aug 13, 2009 · Viewed 23.4k times · Source

I use the <pre> tag in my blog to post code. I know I have to change < to &lt; and > to &gt;. Are any other characters I need to escape for correct html?

Answer

Salman A picture Salman A · Oct 22, 2012

What happens if you use the <pre> tag to display HTML markup on your blog:

<pre>Use a <span style="background: yellow;">span tag with style attribute</span> to hightlight words</pre>

This will pass HTML validation, but does it produce the expected result? No. The correct way is:

<pre>Use a &lt;span style=&quot;background: yellow;&quot;&gt;span tag with style attribute&lt;/span&gt; to hightlight words</pre>

Another example: if you use the pre tag to display some other language code, the HTML encoding is still required:

<pre>if (i && j) return;</pre>

This might produce the expected result but does it pass HTML validation? No. The correct way is:

<pre>if (i &amp;&amp; j) return;</pre>

Long story short, HTML-encode the content of a pre tag just the way you do with other tags.

Related questions

Which characters need to be escaped in HTML?

Are they the same as XML, perhaps plus the space one (&nbsp;)? I've found some huge lists of HTML escape characters but I don't think they must be escaped. I want to know what needs to be escaped.

Read More
HtmlSpecialChars equivalent in Javascript?

Apparently, this is harder to find than I thought it would be. And it even is so simple... Is there a function equivalent to PHP's htmlspecialchars built into Javascript? I know it's fairly easy to implement that yourself, but using …

Read More
Is there a JDK class to do HTML encoding (but not URL encoding)?

I am of course familiar with the java.net.URLEncoder and java.net.URLDecoder classes. However, I only need HTML-style encoding. (I don't want ' ' replaced with '+', etc). I am not aware of any JDK built in …

Read More